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[Clang][CodeGen] Stoping emitting alignment assumes for align_{up,down}

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Now that `align_{up,down}` use `llvm.ptrmask` (as of #71238), the
assume doesn't preserve any information that is not still easily
re-computable.

Closes #71295
This commit is contained in:
Noah Goldstein 2023-11-04 14:56:33 -05:00
parent d0c778c882
commit 590884a860
3 changed files with 0 additions and 12 deletions
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4
clang/lib/CodeGen/CGBuiltin.cpp
View File

@ -19696,10 +19696,6 @@ RValue CodeGenFunction::EmitBuiltinAlignTo(const CallExpr *E, bool AlignUp) {
Result = Builder.CreateIntrinsic(
Intrinsic::ptrmask, {Args.SrcType, Args.IntType},
{SrcForMask, InvertedMask}, nullptr, "aligned_result");
// Emit an alignment assumption to ensure that the new alignment is
// propagated to loads/stores, etc.
emitAlignmentAssumption(Result, E, E->getExprLoc(), Args.Alignment);
} else {
Result = Builder.CreateAnd(SrcForMask, InvertedMask, "aligned_result");
}

4
clang/test/CodeGen/builtin-align-array.c
View File

@ -9,12 +9,10 @@ extern int func(char *c);
// CHECK-NEXT: [[BUF:%.*]] = alloca [1024 x i8], align 16
// CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds [1024 x i8], ptr [[BUF]], i64 0, i64 44
// CHECK-NEXT: [[ALIGNED_RESULT:%.*]] = call ptr @llvm.ptrmask.p0.i64(ptr [[ARRAYIDX]], i64 -16)
// CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(ptr [[ALIGNED_RESULT]], i64 16) ]
// CHECK-NEXT: [[CALL:%.*]] = call i32 @func(ptr noundef [[ALIGNED_RESULT]])
// CHECK-NEXT: [[ARRAYIDX1:%.*]] = getelementptr inbounds [1024 x i8], ptr [[BUF]], i64 0, i64 22
// CHECK-NEXT: [[OVER_BOUNDARY:%.*]] = getelementptr inbounds i8, ptr [[ARRAYIDX1]], i64 31
// CHECK-NEXT: [[ALIGNED_RESULT2:%.*]] = call ptr @llvm.ptrmask.p0.i64(ptr [[OVER_BOUNDARY]], i64 -32)
// CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(ptr [[ALIGNED_RESULT2]], i64 32) ]
// CHECK-NEXT: [[CALL3:%.*]] = call i32 @func(ptr noundef [[ALIGNED_RESULT2]])
// CHECK-NEXT: [[ARRAYIDX4:%.*]] = getelementptr inbounds [1024 x i8], ptr [[BUF]], i64 0, i64 16
// CHECK-NEXT: [[SRC_ADDR:%.*]] = ptrtoint ptr [[ARRAYIDX4]] to i64
@ -35,12 +33,10 @@ int test_array(void) {
// CHECK-NEXT: [[BUF:%.*]] = alloca [1024 x i8], align 32
// CHECK-NEXT: [[ARRAYIDX:%.*]] = getelementptr inbounds [1024 x i8], ptr [[BUF]], i64 0, i64 64
// CHECK-NEXT: [[ALIGNED_RESULT:%.*]] = call ptr @llvm.ptrmask.p0.i64(ptr [[ARRAYIDX]], i64 -16)
// CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(ptr [[ALIGNED_RESULT]], i64 16) ]
// CHECK-NEXT: [[CALL:%.*]] = call i32 @func(ptr noundef [[ALIGNED_RESULT]])
// CHECK-NEXT: [[ARRAYIDX1:%.*]] = getelementptr inbounds [1024 x i8], ptr [[BUF]], i64 0, i64 32
// CHECK-NEXT: [[OVER_BOUNDARY:%.*]] = getelementptr inbounds i8, ptr [[ARRAYIDX1]], i64 31
// CHECK-NEXT: [[ALIGNED_RESULT2:%.*]] = call ptr @llvm.ptrmask.p0.i64(ptr [[OVER_BOUNDARY]], i64 -32)
// CHECK-NEXT: call void @llvm.assume(i1 true) [ "align"(ptr [[ALIGNED_RESULT2]], i64 32) ]
// CHECK-NEXT: [[CALL3:%.*]] = call i32 @func(ptr noundef [[ALIGNED_RESULT2]])
// CHECK-NEXT: ret i32 1
//

4
clang/test/CodeGen/builtin-align.c
View File

@ -119,7 +119,6 @@ _Bool is_aligned(TYPE ptr, unsigned align) {
// CHECK-VOID_PTR-NEXT: [[OVER_BOUNDARY:%.*]] = getelementptr inbounds i8, ptr [[PTR:%.*]], i64 [[MASK]]
// CHECK-VOID_PTR-NEXT: [[INVERTED_MASK:%.*]] = xor i64 [[MASK]], -1
// CHECK-VOID_PTR-NEXT: [[ALIGNED_RESULT:%.*]] = call ptr @llvm.ptrmask.p0.i64(ptr [[OVER_BOUNDARY]], i64 [[INVERTED_MASK]])
// CHECK-VOID_PTR-NEXT: call void @llvm.assume(i1 true) [ "align"(ptr [[ALIGNED_RESULT]], i64 [[ALIGNMENT]]) ]
// CHECK-VOID_PTR-NEXT: ret ptr [[ALIGNED_RESULT]]
//
// CHECK-FLOAT_PTR-LABEL: define {{[^@]+}}@align_up
@ -130,7 +129,6 @@ _Bool is_aligned(TYPE ptr, unsigned align) {
// CHECK-FLOAT_PTR-NEXT: [[OVER_BOUNDARY:%.*]] = getelementptr inbounds i8, ptr [[PTR:%.*]], i64 [[MASK]]
// CHECK-FLOAT_PTR-NEXT: [[INVERTED_MASK:%.*]] = xor i64 [[MASK]], -1
// CHECK-FLOAT_PTR-NEXT: [[ALIGNED_RESULT:%.*]] = call ptr @llvm.ptrmask.p0.i64(ptr [[OVER_BOUNDARY]], i64 [[INVERTED_MASK]])
// CHECK-FLOAT_PTR-NEXT: call void @llvm.assume(i1 true) [ "align"(ptr [[ALIGNED_RESULT]], i64 [[ALIGNMENT]]) ]
// CHECK-FLOAT_PTR-NEXT: ret ptr [[ALIGNED_RESULT]]
//
// CHECK-LONG-LABEL: define {{[^@]+}}@align_up
@ -165,7 +163,6 @@ TYPE align_up(TYPE ptr, unsigned align) {
// CHECK-VOID_PTR-NEXT: [[MASK:%.*]] = sub i64 [[ALIGNMENT]], 1
// CHECK-VOID_PTR-NEXT: [[INVERTED_MASK:%.*]] = xor i64 [[MASK]], -1
// CHECK-VOID_PTR-NEXT: [[ALIGNED_RESULT:%.*]] = call ptr @llvm.ptrmask.p0.i64(ptr [[PTR:%.*]], i64 [[INVERTED_MASK]])
// CHECK-VOID_PTR-NEXT: call void @llvm.assume(i1 true) [ "align"(ptr [[ALIGNED_RESULT]], i64 [[ALIGNMENT]]) ]
// CHECK-VOID_PTR-NEXT: ret ptr [[ALIGNED_RESULT]]
//
// CHECK-FLOAT_PTR-LABEL: define {{[^@]+}}@align_down
@ -175,7 +172,6 @@ TYPE align_up(TYPE ptr, unsigned align) {
// CHECK-FLOAT_PTR-NEXT: [[MASK:%.*]] = sub i64 [[ALIGNMENT]], 1
// CHECK-FLOAT_PTR-NEXT: [[INVERTED_MASK:%.*]] = xor i64 [[MASK]], -1
// CHECK-FLOAT_PTR-NEXT: [[ALIGNED_RESULT:%.*]] = call ptr @llvm.ptrmask.p0.i64(ptr [[PTR:%.*]], i64 [[INVERTED_MASK]])
// CHECK-FLOAT_PTR-NEXT: call void @llvm.assume(i1 true) [ "align"(ptr [[ALIGNED_RESULT]], i64 [[ALIGNMENT]]) ]
// CHECK-FLOAT_PTR-NEXT: ret ptr [[ALIGNED_RESULT]]
//
// CHECK-LONG-LABEL: define {{[^@]+}}@align_down