shylie/llvm-project
1
0
Fork 0
Code Issues Pull Requests Actions 6 Packages Projects Releases Wiki Activity
llvm-project/llvm/test/Transforms/InstCombine/select-binop-cmp.ll
Nikita Popov 21443381c0 Reapply [InstCombine] Replace one-use select operand based on condition 
Relative to the original change, this adds a check that the
instruction on which we're replacing operands is safe to speculatively
execute, because that's what we're effectively doing. We're executing
the instruction with the replaced operand, which is fine if it's pure,
but not fine if can cause side-effects or UB (aka is not speculatable).

Additionally, we cannot (generally) replace operands in phi nodes,
as these may refer to a different loop iteration. This is also covered
by the speculation check.

-----

InstCombine already performs a fold where X == Y ? f(X) : Z is
transformed to X == Y ? f(Y) : Z if f(Y) simplifies. However,
if f(X) only has one use, then we can always directly replace the
use inside the instruction. To actually be profitable, limit it to
the case where Y is a non-expr constant.

This could be further extended to replace uses further up a one-use
instruction chain, but for now this only looks one level up.

Among other things, this also subsumes D94860.

Differential Revision: https://reviews.llvm.org/D94862
2021-01-19 20:26:38 +01:00

1301 lines
44 KiB
LLVM
Raw Blame History

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
declare void @use(<2 x i1>)
declare void @use2(i1)
define i32 @select_xor_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_xor_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = xor i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_xor_icmp2(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_xor_icmp2(
; CHECK-NEXT: [[A_NOT:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A_NOT]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 0
%B = xor i32 %x, %z
%C = select i1 %A, i32 %y, i32 %B
ret i32 %C
}
define i32 @select_xor_icmp_meta(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_xor_icmp_meta(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]], !prof !0
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = xor i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y, !prof !0
ret i32 %C
}
define i32 @select_mul_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_mul_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 1
%B = mul i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_add_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_add_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = add i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_or_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_or_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = or i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_and_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_and_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], -1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, -1
%B = and i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define <2 x i8> @select_xor_icmp_vec(<2 x i8> %x, <2 x i8> %y, <2 x i8> %z) {
; CHECK-LABEL: @select_xor_icmp_vec(
; CHECK-NEXT: [[A:%.*]] = icmp eq <2 x i8> [[X:%.*]], zeroinitializer
; CHECK-NEXT: [[C:%.*]] = select <2 x i1> [[A]], <2 x i8> [[Z:%.*]], <2 x i8> [[Y:%.*]]
; CHECK-NEXT: ret <2 x i8> [[C]]
;
%A = icmp eq <2 x i8> %x, <i8 0, i8 0>
%B = xor <2 x i8> %x, %z
%C = select <2 x i1> %A, <2 x i8> %B, <2 x i8> %y
ret <2 x i8> %C
}
define <2 x i8> @select_xor_icmp_vec_use(<2 x i8> %x, <2 x i8> %y, <2 x i8> %z) {
; CHECK-LABEL: @select_xor_icmp_vec_use(
; CHECK-NEXT: [[A:%.*]] = icmp ne <2 x i8> [[X:%.*]], zeroinitializer
; CHECK-NEXT: call void @use(<2 x i1> [[A]])
; CHECK-NEXT: [[C:%.*]] = select <2 x i1> [[A]], <2 x i8> [[Y:%.*]], <2 x i8> [[Z:%.*]]
; CHECK-NEXT: ret <2 x i8> [[C]]
;
%A = icmp ne <2 x i8> %x, <i8 0, i8 0>
call void @use(<2 x i1> %A)
%B = xor <2 x i8> %x, %z
%C = select <2 x i1> %A, <2 x i8> %y, <2 x i8> %B
ret <2 x i8> %C
}
define i32 @select_xor_inv_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_xor_inv_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = xor i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_xor_inv_icmp2(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_xor_inv_icmp2(
; CHECK-NEXT: [[A:%.*]] = icmp ne i32 [[X:%.*]], 0
; CHECK-NEXT: call void @use2(i1 [[A]])
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Y:%.*]], i32 [[Z:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 0
call void @use2(i1 %A) ; thwart predicate canonicalization
%B = xor i32 %x, %z
%C = select i1 %A, i32 %y, i32 %B
ret i32 %C
}
define float @select_fadd_fcmp(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Z:%.*]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, -0.0
%B = fadd nsz float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
; This is logically equivalent to the previous test - fcmp ignores the sign of 0.0.
define float @select_fadd_fcmp_poszero(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_poszero(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Z:%.*]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 0.0
%B = fadd nsz float %z, %x
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fadd_fcmp_2(float %x, float %y, float %v) {
; CHECK-LABEL: @select_fadd_fcmp_2(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[Z:%.*]] = fadd float [[V:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[Z]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, -0.0
%z = fadd float %v, 0.0 ; cannot produce -0.0
%B = fadd float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; This is logically equivalent to the previous test - fcmp ignores the sign of 0.0.
define float @select_fadd_fcmp_2_poszero(float %x, float %y, float %v) {
; CHECK-LABEL: @select_fadd_fcmp_2_poszero(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[Z:%.*]] = fadd float [[V:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[Z]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, 0.0
%z = fadd float %v, 0.0 ; cannot produce -0.0
%B = fadd float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
define float @select_fadd_fcmp_3(float %x, float %y) {
; CHECK-LABEL: @select_fadd_fcmp_3(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float 6.000000e+00
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, -0.0
%B = fadd float 6.0, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; This is logically equivalent to the previous test - fcmp ignores the sign of 0.0.
define float @select_fadd_fcmp_3_poszero(float %x, float %y) {
; CHECK-LABEL: @select_fadd_fcmp_3_poszero(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float 6.000000e+00
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, 0.0
%B = fadd float 6.0, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
define float @select_fadd_fcmp_4(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_4(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[Z:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, -0.0
%B = fadd nsz float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; This is logically equivalent to the previous test - fcmp ignores the sign of 0.0.
define float @select_fadd_fcmp_4_poszero(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_4_poszero(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[Z:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, 0.0
%B = fadd nsz float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
define float @select_fadd_fcmp_5(float %x, float %y, float %v) {
; CHECK-LABEL: @select_fadd_fcmp_5(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[Z:%.*]] = fadd float [[V:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Z]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, -0.0
%z = fadd float %v, 0.0 ; cannot produce -0.0
%B = fadd float %z, %x
%C = select i1 %A, float %B, float %y
ret float %C
}
; This is logically equivalent to the previous test - fcmp ignores the sign of 0.0.
define float @select_fadd_fcmp_5_poszero(float %x, float %y, float %v) {
; CHECK-LABEL: @select_fadd_fcmp_5_poszero(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[Z:%.*]] = fadd float [[V:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Z]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 0.0
%z = fadd float %v, 0.0 ; cannot produce -0.0
%B = fadd float %z, %x
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fadd_fcmp_6(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_6(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float 6.000000e+00, float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, -0.0
%B = fadd float %x, 6.0
%C = select i1 %A, float %B, float %y
ret float %C
}
; This is logically equivalent to the previous test - fcmp ignores the sign of 0.0.
define float @select_fadd_fcmp_6_poszero(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_6_poszero(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float 6.000000e+00, float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 0.0
%B = fadd float %x, 6.0
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fmul_fcmp(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fmul_fcmp(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Z:%.*]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 1.0
%B = fmul nsz float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fsub_fcmp(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fsub_fcmp(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Z:%.*]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 0.0
%B = fsub nsz float %z, %x
%C = select i1 %A, float %B, float %y
ret float %C
}
; This is logically equivalent to the previous test - fcmp ignores the sign of 0.0.
define float @select_fsub_fcmp_negzero(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fsub_fcmp_negzero(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Z:%.*]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, -0.0
%B = fsub nsz float %z, %x
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fdiv_fcmp(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fdiv_fcmp(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Z:%.*]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 1.0
%B = fdiv nsz float %z, %x
%C = select i1 %A, float %B, float %y
ret float %C
}
define i32 @select_sub_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sub_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = sub i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sub_icmp_2(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sub_icmp_2(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: call void @use2(i1 [[A]])
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
call void @use2(i1 %A)
%B = sub i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sub_icmp_3(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sub_icmp_3(
; CHECK-NEXT: [[A:%.*]] = icmp ne i32 [[X:%.*]], 0
; CHECK-NEXT: call void @use2(i1 [[A]])
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Y:%.*]], i32 [[Z:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 0
call void @use2(i1 %A)
%B = sub i32 %z, %x
%C = select i1 %A, i32 %y, i32 %B
ret i32 %C
}
define <2 x i8> @select_sub_icmp_vec(<2 x i8> %x, <2 x i8> %y, <2 x i8> %z) {
; CHECK-LABEL: @select_sub_icmp_vec(
; CHECK-NEXT: [[A:%.*]] = icmp eq <2 x i8> [[X:%.*]], zeroinitializer
; CHECK-NEXT: [[C:%.*]] = select <2 x i1> [[A]], <2 x i8> [[Z:%.*]], <2 x i8> [[Y:%.*]]
; CHECK-NEXT: ret <2 x i8> [[C]]
;
%A = icmp eq <2 x i8> %x, <i8 0, i8 0>
%B = sub <2 x i8> %z, %x
%C = select <2 x i1> %A, <2 x i8> %B, <2 x i8> %y
ret <2 x i8> %C
}
define i32 @select_shl_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_shl_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp ne i32 [[X:%.*]], 0
; CHECK-NEXT: call void @use2(i1 [[A]])
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Y:%.*]], i32 [[Z:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 0
call void @use2(i1 %A) ; thwart predicate canonicalization
%B = shl i32 %z, %x
%C = select i1 %A, i32 %y, i32 %B
ret i32 %C
}
define i32 @select_lshr_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_lshr_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = lshr i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_ashr_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_ashr_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp ne i32 [[X:%.*]], 0
; CHECK-NEXT: call void @use2(i1 [[A]])
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Y:%.*]], i32 [[Z:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 0
call void @use2(i1 %A) ; thwart predicate canonicalization
%B = ashr i32 %z, %x
%C = select i1 %A, i32 %y, i32 %B
ret i32 %C
}
define i32 @select_udiv_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_udiv_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 1
%B = udiv i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sdiv_icmp(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sdiv_icmp(
; CHECK-NEXT: [[A:%.*]] = icmp ne i32 [[X:%.*]], 1
; CHECK-NEXT: call void @use2(i1 [[A]])
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[Y:%.*]], i32 [[Z:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 1
call void @use2(i1 %A) ; thwart predicate canonicalization
%B = sdiv i32 %z, %x
%C = select i1 %A, i32 %y, i32 %B
ret i32 %C
}
; Negative tests
define i32 @select_xor_icmp_bad_1(i32 %x, i32 %y, i32 %z, i32 %k) {
; CHECK-LABEL: @select_xor_icmp_bad_1(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], [[K:%.*]]
; CHECK-NEXT: [[B:%.*]] = xor i32 [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, %k
%B = xor i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_xor_icmp_bad_2(i32 %x, i32 %y, i32 %z, i32 %k) {
; CHECK-LABEL: @select_xor_icmp_bad_2(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[B:%.*]] = xor i32 [[K:%.*]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = xor i32 %k, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_xor_icmp_bad_3(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_xor_icmp_bad_3(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 3
; CHECK-NEXT: [[B:%.*]] = xor i32 [[Z:%.*]], 3
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 3
%B = xor i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_xor_fcmp_bad_4(i32 %x, i32 %y, i32 %z, float %k) {
; CHECK-LABEL: @select_xor_fcmp_bad_4(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[K:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = xor i32 [[X:%.*]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = fcmp oeq float %k, 0.0
%B = xor i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_xor_icmp_bad_5(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_xor_icmp_bad_5(
; CHECK-NEXT: [[A_NOT:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[B:%.*]] = xor i32 [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A_NOT]], i32 [[Y:%.*]], i32 [[B]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 0
%B = xor i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_xor_icmp_bad_6(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_xor_icmp_bad_6(
; CHECK-NEXT: [[A_NOT:%.*]] = icmp eq i32 [[X:%.*]], 1
; CHECK-NEXT: [[B:%.*]] = xor i32 [[Z:%.*]], 1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A_NOT]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 1
%B = xor i32 %x, %z
%C = select i1 %A, i32 %y, i32 %B
ret i32 %C
}
define <2 x i8> @select_xor_icmp_vec_bad(<2 x i8> %x, <2 x i8> %y, <2 x i8> %z) {
; CHECK-LABEL: @select_xor_icmp_vec_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq <2 x i8> [[X:%.*]], <i8 5, i8 3>
; CHECK-NEXT: [[B:%.*]] = xor <2 x i8> [[Z:%.*]], <i8 5, i8 3>
; CHECK-NEXT: [[C:%.*]] = select <2 x i1> [[A]], <2 x i8> [[B]], <2 x i8> [[Y:%.*]]
; CHECK-NEXT: ret <2 x i8> [[C]]
;
%A = icmp eq <2 x i8> %x, <i8 5, i8 3>
%B = xor <2 x i8> %x, %z
%C = select <2 x i1> %A, <2 x i8> %B, <2 x i8> %y
ret <2 x i8> %C
}
; Folding this would only be legal if we sanitized undef to 0.
define <2 x i8> @select_xor_icmp_vec_undef(<2 x i8> %x, <2 x i8> %y, <2 x i8> %z) {
; CHECK-LABEL: @select_xor_icmp_vec_undef(
; CHECK-NEXT: [[A:%.*]] = icmp eq <2 x i8> [[X:%.*]], <i8 0, i8 undef>
; CHECK-NEXT: [[B:%.*]] = xor <2 x i8> [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select <2 x i1> [[A]], <2 x i8> [[B]], <2 x i8> [[Y:%.*]]
; CHECK-NEXT: ret <2 x i8> [[C]]
;
%A = icmp eq <2 x i8> %x, <i8 0, i8 undef>
%B = xor <2 x i8> %x, %z
%C = select <2 x i1> %A, <2 x i8> %B, <2 x i8> %y
ret <2 x i8> %C
}
define i32 @select_mul_icmp_bad(i32 %x, i32 %y, i32 %z, i32 %k) {
; CHECK-LABEL: @select_mul_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 3
; CHECK-NEXT: [[B:%.*]] = mul i32 [[Z:%.*]], 3
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 3
%B = mul i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_add_icmp_bad(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_add_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 1
; CHECK-NEXT: [[B:%.*]] = add i32 [[Z:%.*]], 1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 1
%B = add i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_and_icmp_zero(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_and_icmp_zero(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 0, i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = and i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_or_icmp_bad(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_or_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 3
; CHECK-NEXT: [[B:%.*]] = or i32 [[Z:%.*]], 3
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 3
%B = or i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
; Invalid identity constant for FP op
define float @select_fadd_fcmp_bad(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], -1.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd nsz float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, -1.0
%B = fadd nsz float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
; Invalid comparison type
define float @select_fadd_fcmp_bad_2(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_2(
; CHECK-NEXT: [[A:%.*]] = fcmp ueq float [[X:%.*]], -1.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp ueq float %x, -1.0
%B = fadd float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
; Invalid comparison type
define float @select_fadd_fcmp_bad_3(float %x, float %y, float %z, float %k) {
; CHECK-LABEL: @select_fadd_fcmp_bad_3(
; CHECK-NEXT: [[A:%.*]] = fcmp one float [[X:%.*]], [[K:%.*]]
; CHECK-NEXT: [[B:%.*]] = fadd float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp one float %x, %k
%B = fadd float %x, %z
%C = select i1 %A, float %y, float %B
ret float %C
}
; Invalid order of operands of select
define float @select_fadd_fcmp_bad_4(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_4(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, -0.0
%B = fadd float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
; Invalid comparison type
define float @select_fadd_fcmp_bad_5(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_5(
; CHECK-NEXT: [[A:%.*]] = fcmp one float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd nsz float [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp one float %x, -0.0
%B = fadd nsz float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; Invalid order of operands of select
define float @select_fadd_fcmp_bad_6(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_6(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd nsz float [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, -0.0
%B = fadd nsz float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; Do not transform if we have signed zeros and if Z is possibly negative zero
define float @select_fadd_fcmp_bad_7(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_7(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, -0.0
%B = fadd float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
; Invalid comparison type
define float @select_fadd_fcmp_bad_8(float %x, float %y, float %v) {
; CHECK-LABEL: @select_fadd_fcmp_bad_8(
; CHECK-NEXT: [[A:%.*]] = fcmp one float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[Z:%.*]] = fadd float [[V:%.*]], -1.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd float [[Z]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp one float %x, -0.0
%z = fadd float %v, -1.0
%B = fadd float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; Invalid comparison type
define float @select_fadd_fcmp_bad_9(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_9(
; CHECK-NEXT: [[A:%.*]] = fcmp one float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd nsz float [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp one float %x, -0.0
%B = fadd nsz float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; Invalid comparison type
define float @select_fadd_fcmp_bad_10(float %x, float %y, float %v) {
; CHECK-LABEL: @select_fadd_fcmp_bad_10(
; CHECK-NEXT: [[A:%.*]] = fcmp one float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[Z:%.*]] = fadd float [[V:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd float [[Z]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp one float %x, -0.0
%z = fadd float %v, 0.0 ; cannot produce -0.0
%B = fadd float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; Do not transform if Z is possibly negative zero
define float @select_fadd_fcmp_bad_11(float %x, float %y, float %v) {
; CHECK-LABEL: @select_fadd_fcmp_bad_11(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[Z:%.*]] = fadd float [[V:%.*]], -1.000000e+00
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[Z]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, -0.0
%z = fadd float %v, -1.0
%B = fadd nsz float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; Do not transform if we have signed zeros and if Z is possibly negative zero
define float @select_fadd_fcmp_bad_12(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_12(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd float [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, -0.0
%B = fadd float %z, %x
%C = select i1 %A, float %y, float %B
ret float %C
}
; Invalid order of operands of select
define float @select_fadd_fcmp_bad_13(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_13(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd nsz float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, -0.0
%B = fadd nsz float %x, %z
%C = select i1 %A, float %y, float %B
ret float %C
}
; Invalid identity constant for FP op
define float @select_fadd_fcmp_bad_14(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fadd_fcmp_bad_14(
; CHECK-NEXT: [[A:%.*]] = fcmp une float [[X:%.*]], -1.000000e+00
; CHECK-NEXT: [[B:%.*]] = fadd nsz float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[Y:%.*]], float [[B]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp une float %x, -1.0
%B = fadd nsz float %x, %z
%C = select i1 %A, float %y, float %B
ret float %C
}
define float @select_fmul_fcmp_bad(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fmul_fcmp_bad(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 3.000000e+00
; CHECK-NEXT: [[B:%.*]] = fmul nsz float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 3.0
%B = fmul nsz float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fmul_fcmp_bad_2(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fmul_fcmp_bad_2(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[B:%.*]] = fmul float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 1.0
%B = fmul float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fmul_icmp_bad(float %x, float %y, float %z, i32 %k) {
; CHECK-LABEL: @select_fmul_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[K:%.*]], 0
; CHECK-NEXT: [[B:%.*]] = fmul float [[X:%.*]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = icmp eq i32 %k, 0
%B = fmul float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fmul_icmp_bad_2(float %x, float %y, float %z, i32 %k) {
; CHECK-LABEL: @select_fmul_icmp_bad_2(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[K:%.*]], 0
; CHECK-NEXT: [[B:%.*]] = fmul nsz float [[X:%.*]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = icmp eq i32 %k, 0
%B = fmul nsz float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fdiv_fcmp_bad(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fdiv_fcmp_bad(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[B:%.*]] = fdiv float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 1.0
%B = fdiv float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fdiv_fcmp_bad_2(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fdiv_fcmp_bad_2(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 3.000000e+00
; CHECK-NEXT: [[B:%.*]] = fdiv nsz float [[X]], [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 3.0
%B = fdiv nsz float %x, %z
%C = select i1 %A, float %B, float %y
ret float %C
}
; The transform is not valid when x = -0.0 and z = -0.0
; (optimized code would return -0.0, but this returns +0.0).
define float @select_fsub_fcmp_bad(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fsub_fcmp_bad(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[B:%.*]] = fsub float [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 0.0
%B = fsub float %z, %x
%C = select i1 %A, float %B, float %y
ret float %C
}
define float @select_fsub_fcmp_bad_2(float %x, float %y, float %z) {
; CHECK-LABEL: @select_fsub_fcmp_bad_2(
; CHECK-NEXT: [[A:%.*]] = fcmp oeq float [[X:%.*]], 1.000000e+00
; CHECK-NEXT: [[B:%.*]] = fsub nsz float [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], float [[B]], float [[Y:%.*]]
; CHECK-NEXT: ret float [[C]]
;
%A = fcmp oeq float %x, 1.0
%B = fsub nsz float %z, %x
%C = select i1 %A, float %B, float %y
ret float %C
}
define i32 @select_sub_icmp_bad(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sub_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[B:%.*]] = sub i32 0, [[Z:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = sub i32 %x, %z
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sub_icmp_bad_2(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sub_icmp_bad_2(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 1
; CHECK-NEXT: [[B:%.*]] = add i32 [[Z:%.*]], -1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 1
%B = sub i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sub_icmp_bad_3(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sub_icmp_bad_3(
; CHECK-NEXT: [[A:%.*]] = icmp ne i32 [[X:%.*]], 0
; CHECK-NEXT: call void @use2(i1 [[A]])
; CHECK-NEXT: [[B:%.*]] = sub i32 [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 0
call void @use2(i1 %A)
%B = sub i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sub_icmp_4(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sub_icmp_4(
; CHECK-NEXT: [[A:%.*]] = icmp ne i32 [[X:%.*]], 0
; CHECK-NEXT: call void @use2(i1 [[A]])
; CHECK-NEXT: [[B:%.*]] = sub i32 [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp ne i32 %x, 0
call void @use2(i1 %A)
%B = sub i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sub_icmp_bad_4(i32 %x, i32 %y, i32 %z, i32 %k) {
; CHECK-LABEL: @select_sub_icmp_bad_4(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[B:%.*]] = sub i32 [[Z:%.*]], [[K:%.*]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 0
%B = sub i32 %z, %k
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sub_icmp_bad_5(i32 %x, i32 %y, i32 %z, i32 %k) {
; CHECK-LABEL: @select_sub_icmp_bad_5(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], [[K:%.*]]
; CHECK-NEXT: [[B:%.*]] = sub i32 [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, %k
%B = sub i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_shl_icmp_bad(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_shl_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 1
; CHECK-NEXT: [[B:%.*]] = shl i32 [[Z:%.*]], 1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 1
%B = shl i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_lshr_icmp_bad(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_lshr_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 1
; CHECK-NEXT: [[B:%.*]] = lshr i32 [[Z:%.*]], 1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 1
%B = lshr i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_ashr_icmp_bad(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_ashr_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 1
; CHECK-NEXT: [[B:%.*]] = ashr i32 [[Z:%.*]], 1
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 1
%B = ashr i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_udiv_icmp_bad(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_udiv_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 3
; CHECK-NEXT: [[B:%.*]] = udiv i32 [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 3
%B = udiv i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
define i32 @select_sdiv_icmp_bad(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_sdiv_icmp_bad(
; CHECK-NEXT: [[A:%.*]] = icmp eq i32 [[X:%.*]], 3
; CHECK-NEXT: [[B:%.*]] = sdiv i32 [[Z:%.*]], [[X]]
; CHECK-NEXT: [[C:%.*]] = select i1 [[A]], i32 [[B]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[C]]
;
%A = icmp eq i32 %x, 3
%B = sdiv i32 %z, %x
%C = select i1 %A, i32 %B, i32 %y
ret i32 %C
}
; Can replace %x with 0, because sub is only used in the select.
define i32 @select_replace_one_use(i32 %x, i32 %y) {
; CHECK-LABEL: @select_replace_one_use(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[SUB:%.*]] = sub i32 0, [[Y:%.*]]
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[SUB]], i32 [[Y]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 0
%sub = sub i32 %x, %y
%s = select i1 %c, i32 %sub, i32 %y
ret i32 %s
}
; Can not replace %x with 0, because %sub has other uses as well.
define i32 @select_replace_multi_use(i32 %x, i32 %y) {
; CHECK-LABEL: @select_replace_multi_use(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[X]], [[Y:%.*]]
; CHECK-NEXT: call void @use_i32(i32 [[SUB]])
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[SUB]], i32 [[Y]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 0
%sub = sub i32 %x, %y
call void @use_i32(i32 %sub)
%s = select i1 %c, i32 %sub, i32 %y
ret i32 %s
}
; Case where the replacement allows the instruction to fold away.
define i32 @select_replace_fold(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_replace_fold(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[Z:%.*]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 0
%fshr = call i32 @llvm.fshr.i32(i32 %y, i32 %z, i32 %x)
%s = select i1 %c, i32 %fshr, i32 %y
ret i32 %s
}
; Case where the use of %x is in a nested instruction.
; FIXME: We only perform replacements one level up right now.
define i32 @select_replace_nested(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_replace_nested(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[SUB:%.*]] = sub i32 [[Y:%.*]], [[X]]
; CHECK-NEXT: [[ADD:%.*]] = add i32 [[SUB]], [[Z:%.*]]
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[ADD]], i32 [[Y]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 0
%sub = sub i32 %y, %x
%add = add i32 %sub, %z
%s = select i1 %c, i32 %add, i32 %y
ret i32 %s
}
; Do not replace with constant expressions. The profitability in this case is
; unclear, and such replacements have historically lead to infinite combine
; loops.
define i32 @select_replace_constexpr(i32 %x, i32 %y, i32 %z) {
; CHECK-LABEL: @select_replace_constexpr(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], ptrtoint (i32* @g to i32)
; CHECK-NEXT: [[ADD:%.*]] = add i32 [[X]], [[Y:%.*]]
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[ADD]], i32 [[Z:%.*]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, ptrtoint (i32* @g to i32)
%add = add i32 %x, %y
%s = select i1 %c, i32 %add, i32 %z
ret i32 %s
}
; Don't replace with a potentially undef constant, as undef could evaluate
; to different values for both uses.
define <2 x i32> @select_replace_undef(<2 x i32> %x, <2 x i32> %y) {
; CHECK-LABEL: @select_replace_undef(
; CHECK-NEXT: [[C:%.*]] = icmp eq <2 x i32> [[X:%.*]], <i32 0, i32 undef>
; CHECK-NEXT: [[SUB:%.*]] = sub <2 x i32> [[X]], [[Y:%.*]]
; CHECK-NEXT: [[S:%.*]] = select <2 x i1> [[C]], <2 x i32> [[SUB]], <2 x i32> [[Y]]
; CHECK-NEXT: ret <2 x i32> [[S]]
;
%c = icmp eq <2 x i32> %x, <i32 0, i32 undef>
%sub = sub <2 x i32> %x, %y
%s = select <2 x i1> %c, <2 x i32> %sub, <2 x i32> %y
ret <2 x i32> %s
}
; We can replace the call arguments, as the call is speculatable.
define i32 @select_replace_call_speculatable(i32 %x, i32 %y) {
; CHECK-LABEL: @select_replace_call_speculatable(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[CALL:%.*]] = call i32 @call_speculatable(i32 0, i32 0)
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[CALL]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 0
%call = call i32 @call_speculatable(i32 %x, i32 %x)
%s = select i1 %c, i32 %call, i32 %y
ret i32 %s
}
; We can't replace the call arguments, as the call is not speculatable. We
; may end up changing side-effects or causing undefined behavior.
define i32 @select_replace_call_non_speculatable(i32 %x, i32 %y) {
; CHECK-LABEL: @select_replace_call_non_speculatable(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[CALL:%.*]] = call i32 @call_non_speculatable(i32 [[X]], i32 [[X]])
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[CALL]], i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 0
%call = call i32 @call_non_speculatable(i32 %x, i32 %x)
%s = select i1 %c, i32 %call, i32 %y
ret i32 %s
}
; We can replace %x by 2 here, because division by two cannot cause UB.
; FIXME: As we check speculation prior to replacement, we don't catch this.
define i32 @select_replace_sdiv_speculatable(i32 %x, i32 %y) {
; CHECK-LABEL: @select_replace_sdiv_speculatable(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 2
; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[Y:%.*]], [[X]]
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[DIV]], i32 [[Y]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 2
%div = sdiv i32 %y, %x
%s = select i1 %c, i32 %div, i32 %y
ret i32 %s
}
; We cannot replace %x by -1, because division by -1 can cause UB.
define i32 @select_replace_sdiv_non_speculatable(i32 %x, i32 %y) {
; CHECK-LABEL: @select_replace_sdiv_non_speculatable(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], -1
; CHECK-NEXT: [[DIV:%.*]] = sdiv i32 [[Y:%.*]], [[X]]
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[DIV]], i32 [[Y]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, -1
%div = sdiv i32 %y, %x
%s = select i1 %c, i32 %div, i32 %y
ret i32 %s
}
; We can replace %x by 2 here, because division by two cannot cause UB.
; FIXME: As we check speculation prior to replacement, we don't catch this.
define i32 @select_replace_udiv_speculatable(i32 %x, i32 %y) {
; CHECK-LABEL: @select_replace_udiv_speculatable(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 2
; CHECK-NEXT: [[DIV:%.*]] = udiv i32 [[Y:%.*]], [[X]]
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[DIV]], i32 [[Y]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 2
%div = udiv i32 %y, %x
%s = select i1 %c, i32 %div, i32 %y
ret i32 %s
}
; We can't replace %x by 0 here, because that would cause UB. However,
; replacing the udiv result by poisong is fine.
define i32 @select_replace_udiv_non_speculatable(i32 %x, i32 %y) {
; CHECK-LABEL: @select_replace_udiv_non_speculatable(
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[X:%.*]], 0
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 poison, i32 [[Y:%.*]]
; CHECK-NEXT: ret i32 [[S]]
;
%c = icmp eq i32 %x, 0
%div = udiv i32 %y, %x
%s = select i1 %c, i32 %div, i32 %y
ret i32 %s
}
; We can't replace %i in the phi node here, because it refers to %i from
; the previous loop iteration, not the current one.
define void @select_replace_phi(i32 %x) {
; CHECK-LABEL: @select_replace_phi(
; CHECK-NEXT: entry:
; CHECK-NEXT: br label [[LOOP:%.*]]
; CHECK: loop:
; CHECK-NEXT: [[I:%.*]] = phi i32 [ 0, [[ENTRY:%.*]] ], [ [[I_NEXT:%.*]], [[LOOP]] ]
; CHECK-NEXT: [[I_PREV:%.*]] = phi i32 [ -1, [[ENTRY]] ], [ [[I]], [[LOOP]] ]
; CHECK-NEXT: [[I_NEXT]] = add i32 [[I]], 1
; CHECK-NEXT: [[C:%.*]] = icmp eq i32 [[I]], 0
; CHECK-NEXT: [[S:%.*]] = select i1 [[C]], i32 [[I_PREV]], i32 2
; CHECK-NEXT: call void @use_i32(i32 [[S]])
; CHECK-NEXT: br label [[LOOP]]
;
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
%i.prev = phi i32 [ -1, %entry], [ %i, %loop ]
%i.next = add i32 %i, 1
%c = icmp eq i32 %i, 0
%s = select i1 %c, i32 %i.prev, i32 2
call void @use_i32(i32 %s)
br label %loop
}
@g = global i32 0
declare i32 @llvm.fshr.i32(i32, i32, i32)
declare i32 @call_speculatable(i32, i32) speculatable
declare i32 @call_non_speculatable(i32, i32)
declare void @use_i32(i32)
!0 = !{!"branch_weights", i32 2, i32 10}
Reference in New Issue View Git Blame Copy Permalink