llvm-project/llvm/test/CodeGen/PowerPC/aix-lower-arbitrary-sized-ints.ll
Amy Kwan f48a8da342
[AIX] Handle arbitrary sized integers when lowering formal arguments passed on the stack (#149351)
When arbitrary sized (non-simple type, or non-power of two types)
integers are passed on the stack, these integers are not handled when
lowering formal arguments on AIX as we always assume we will encounter
simple type integers.

However, it is possible for frontends to generate arbitrary sized
immediate values in IR. Specifically in rustc, it will generate an
integer value in LLVM IR for small structures that are less than a
pointer size, which is done for optimization purposes for the Rust ABI.
For example, if a Rust structure of three characters is passed into
function on the stack,
```
struct my_struct {
  field1: u8,
  field2: u8,
  field3: u8,
}
```
This will generate an `i24` type in LLVM IR.

Currently, it is not obvious for the backend to distinguish an integer
versus something that wasn't an integer to begin with (such as a
struct), and the latter case would not have an extend on the parameter.
Thus, this PR allows us to perform a truncation and extend on integers,
both non-simple and simple types.
2025-08-01 08:01:26 -04:00

62 lines
2.0 KiB
LLVM

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
; RUN: llc --verify-machineinstrs -mtriple powerpc-ibm-aix-xcoff \
; RUN: -ppc-asm-full-reg-names -mcpu=pwr8 < %s | \
; RUN: FileCheck %s --check-prefixes=CHECK,CHECK32
; RUN: llc --verify-machineinstrs -mtriple powerpc64-ibm-aix-xcoff \
; RUN: -ppc-asm-full-reg-names -mcpu=pwr8 < %s | \
; RUN: FileCheck %s --check-prefixes=CHECK,CHECK64
define ptr @lower_args(ptr %_0, i32 %0, i32 %1, i32 %2, i32 %3, ptr %4, ptr %5, i64 %6, i24 %7) {
; CHECK-LABEL: lower_args:
; CHECK: # %bb.0: # %entry
; CHECK-NEXT: blr
entry:
ret ptr %_0
}
define i32 @lower_args_withops_zeroext(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e, i32 %f, i32 %g, i32 %h, i24 %i) {
; CHECK32-LABEL: lower_args_withops_zeroext:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: lwz r3, 56(r1)
; CHECK32-NEXT: addi r3, r3, 255
; CHECK32-NEXT: clrlwi r3, r3, 8
; CHECK32-NEXT: blr
;
; CHECK64-LABEL: lower_args_withops_zeroext:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: lwz r3, 116(r1)
; CHECK64-NEXT: addi r3, r3, 255
; CHECK64-NEXT: clrldi r3, r3, 40
; CHECK64-NEXT: blr
entry:
%0 = add i24 %i, 255
%1 = zext i24 %0 to i32
ret i32 %1
}
define i32 @lower_args_withops_signext(i32 %a, i32 %b, i32 %c, i32 %d, i32 %e, i32 %f, i32 %g, i32 %h, i24 signext %i) {
; CHECK32-LABEL: lower_args_withops_signext:
; CHECK32: # %bb.0: # %entry
; CHECK32-NEXT: lwz r3, 56(r1)
; CHECK32-NEXT: slwi r3, r3, 8
; CHECK32-NEXT: srawi r3, r3, 8
; CHECK32-NEXT: slwi r3, r3, 8
; CHECK32-NEXT: addi r3, r3, 22272
; CHECK32-NEXT: srawi r3, r3, 8
; CHECK32-NEXT: blr
;
; CHECK64-LABEL: lower_args_withops_signext:
; CHECK64: # %bb.0: # %entry
; CHECK64-NEXT: lwz r3, 116(r1)
; CHECK64-NEXT: slwi r3, r3, 8
; CHECK64-NEXT: srawi r3, r3, 8
; CHECK64-NEXT: addi r3, r3, 87
; CHECK64-NEXT: sldi r3, r3, 40
; CHECK64-NEXT: sradi r3, r3, 40
; CHECK64-NEXT: blr
entry:
%0 = add i24 %i, 87
%1 = sext i24 %0 to i32
ret i32 %1
}