[llvm] [InstCombine] Fix FMF propagation in `foldSelectIntoOp` (PR #114356)
Yingwei Zheng via llvm-commits
llvm-commits at lists.llvm.org
Wed Oct 30 22:02:40 PDT 2024
https://github.com/dtcxzyw created https://github.com/llvm/llvm-project/pull/114356
Closes https://github.com/llvm/llvm-project/issues/113423.
>From f15f640f886aa806e390f3e74ca479b00571344d Mon Sep 17 00:00:00 2001
From: Yingwei Zheng <dtcxzyw2333 at gmail.com>
Date: Thu, 31 Oct 2024 12:38:11 +0800
Subject: [PATCH] [InstCombine] Fix FMF propagation in `foldSelectIntoOp`
---
.../InstCombine/InstCombineSelect.cpp | 5 ++---
.../InstCombine/fold-select-fmul-if-zero.ll | 18 +++++++++---------
.../select-binop-foldable-floating-point.ll | 16 ++++++++--------
3 files changed, 19 insertions(+), 20 deletions(-)
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
index c5f39a4c381ed1..9e193e7faa8ac3 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineSelect.cpp
@@ -529,9 +529,6 @@ Instruction *InstCombinerImpl::foldSelectIntoOp(SelectInst &SI, Value *TrueVal,
if (!OpToFold)
return nullptr;
- // TODO: We probably ought to revisit cases where the select and FP
- // instructions have different flags and add tests to ensure the
- // behaviour is correct.
FastMathFlags FMF;
if (isa<FPMathOperator>(&SI))
FMF = SI.getFastMathFlags();
@@ -564,6 +561,8 @@ Instruction *InstCombinerImpl::foldSelectIntoOp(SelectInst &SI, Value *TrueVal,
BinaryOperator *BO =
BinaryOperator::Create(TVI->getOpcode(), FalseVal, NewSel);
BO->copyIRFlags(TVI);
+ if (isa<FPMathOperator>(&SI))
+ BO->andIRFlags(NewSel);
return BO;
};
diff --git a/llvm/test/Transforms/InstCombine/fold-select-fmul-if-zero.ll b/llvm/test/Transforms/InstCombine/fold-select-fmul-if-zero.ll
index 1c28b151825c12..caf38c676e20d7 100644
--- a/llvm/test/Transforms/InstCombine/fold-select-fmul-if-zero.ll
+++ b/llvm/test/Transforms/InstCombine/fold-select-fmul-if-zero.ll
@@ -468,7 +468,7 @@ define float @fmul_by_var_if_0_oeq_zero_f32_nsz_fmul(float %x, float %y) {
; CHECK-LABEL: @fmul_by_var_if_0_oeq_zero_f32_nsz_fmul(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[Y:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nsz float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
@@ -482,7 +482,7 @@ define float @fmul_by_var_if_0_oeq_zero_f32_nsz_ninf_fmul(float %x, float %y) {
; CHECK-LABEL: @fmul_by_var_if_0_oeq_zero_f32_nsz_ninf_fmul(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[Y:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul ninf nsz float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
@@ -496,7 +496,7 @@ define float @fmul_by_var_if_0_oeq_zero_f32_nsz_nnan_fmul(float %x, float %y) {
; CHECK-LABEL: @fmul_by_var_if_0_oeq_zero_f32_nsz_nnan_fmul(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[Y:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan nsz float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
@@ -510,7 +510,7 @@ define float @fmul_by_var_if_0_oeq_zero_f32_nnan_ninf_fmul(float %x, float %y) {
; CHECK-LABEL: @fmul_by_var_if_0_oeq_zero_f32_nnan_ninf_fmul(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[Y:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan ninf float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
@@ -559,7 +559,7 @@ define float @fmul_by_var_if_0_oeq_zero_f32_fmul_nnan_ninf_nsz(float %x, float %
; CHECK-LABEL: @fmul_by_var_if_0_oeq_zero_f32_fmul_nnan_ninf_nsz(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[Y:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan ninf nsz float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
@@ -572,7 +572,7 @@ define float @fmul_by_var_if_0_oeq_zero_f32_fmul_nnan_ninf_nsz_commuted(float %x
; CHECK-LABEL: @fmul_by_var_if_0_oeq_zero_f32_fmul_nnan_ninf_nsz_commuted(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[Y:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan ninf nsz float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
@@ -586,7 +586,7 @@ define float @fmul_by_var_if_0_oeq_zero_f32_fmul_nnan_ninf_select_known_never_ne
; CHECK-LABEL: @fmul_by_var_if_0_oeq_zero_f32_fmul_nnan_ninf_select_known_never_negzero(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[Y:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan ninf float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
@@ -599,7 +599,7 @@ define float @fmul_by_var_if_0_oeq_zero_f32_fmul_nnan_ninf_select_known_never_ne
; CHECK-LABEL: @fmul_by_var_if_0_oeq_zero_f32_fmul_nnan_ninf_select_known_never_negzero_negsub(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[Y:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan ninf float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
@@ -706,7 +706,7 @@ define float @fmul_by_self_if_0_oeq_zero_f32_fmul_nnan_ninf_nsz(float %x) {
; CHECK-LABEL: @fmul_by_self_if_0_oeq_zero_f32_fmul_nnan_ninf_nsz(
; CHECK-NEXT: [[X_IS_ZERO:%.*]] = fcmp oeq float [[X:%.*]], 0.000000e+00
; CHECK-NEXT: [[SCALED_X:%.*]] = select nnan i1 [[X_IS_ZERO]], float [[X]], float 1.000000e+00
-; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan ninf nsz float [[X]], [[SCALED_X]]
+; CHECK-NEXT: [[SCALED_IF_DENORMAL:%.*]] = fmul nnan float [[X]], [[SCALED_X]]
; CHECK-NEXT: ret float [[SCALED_IF_DENORMAL]]
;
%x.is.zero = fcmp oeq float %x, 0.0
diff --git a/llvm/test/Transforms/InstCombine/select-binop-foldable-floating-point.ll b/llvm/test/Transforms/InstCombine/select-binop-foldable-floating-point.ll
index e5ad312bb85c17..df02eb7bb83ac6 100644
--- a/llvm/test/Transforms/InstCombine/select-binop-foldable-floating-point.ll
+++ b/llvm/test/Transforms/InstCombine/select-binop-foldable-floating-point.ll
@@ -48,7 +48,7 @@ define float @select_nnan_fadd_swapped(i1 %cond, float %A, float %B) {
define float @select_nnan_fadd_fast_math(i1 %cond, float %A, float %B) {
; CHECK-LABEL: @select_nnan_fadd_fast_math(
; CHECK-NEXT: [[C:%.*]] = select nnan i1 [[COND:%.*]], float [[B:%.*]], float -0.000000e+00
-; CHECK-NEXT: [[D:%.*]] = fadd fast float [[A:%.*]], [[C]]
+; CHECK-NEXT: [[D:%.*]] = fadd nnan float [[A:%.*]], [[C]]
; CHECK-NEXT: ret float [[D]]
;
%C = fadd fast float %A, %B
@@ -59,7 +59,7 @@ define float @select_nnan_fadd_fast_math(i1 %cond, float %A, float %B) {
define float @select_nnan_fadd_swapped_fast_math(i1 %cond, float %A, float %B) {
; CHECK-LABEL: @select_nnan_fadd_swapped_fast_math(
; CHECK-NEXT: [[C:%.*]] = select nnan i1 [[COND:%.*]], float -0.000000e+00, float [[B:%.*]]
-; CHECK-NEXT: [[D:%.*]] = fadd fast float [[A:%.*]], [[C]]
+; CHECK-NEXT: [[D:%.*]] = fadd nnan float [[A:%.*]], [[C]]
; CHECK-NEXT: ret float [[D]]
;
%C = fadd fast float %A, %B
@@ -125,7 +125,7 @@ define float @select_nnan_fmul_swapped(i1 %cond, float %A, float %B) {
define float @select_nnan_fmul_fast_math(i1 %cond, float %A, float %B) {
; CHECK-LABEL: @select_nnan_fmul_fast_math(
; CHECK-NEXT: [[C:%.*]] = select nnan i1 [[COND:%.*]], float [[B:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[D:%.*]] = fmul fast float [[A:%.*]], [[C]]
+; CHECK-NEXT: [[D:%.*]] = fmul nnan float [[A:%.*]], [[C]]
; CHECK-NEXT: ret float [[D]]
;
%C = fmul fast float %A, %B
@@ -136,7 +136,7 @@ define float @select_nnan_fmul_fast_math(i1 %cond, float %A, float %B) {
define float @select_nnan_fmul_swapped_fast_math(i1 %cond, float %A, float %B) {
; CHECK-LABEL: @select_nnan_fmul_swapped_fast_math(
; CHECK-NEXT: [[C:%.*]] = select nnan i1 [[COND:%.*]], float 1.000000e+00, float [[B:%.*]]
-; CHECK-NEXT: [[D:%.*]] = fmul fast float [[A:%.*]], [[C]]
+; CHECK-NEXT: [[D:%.*]] = fmul nnan float [[A:%.*]], [[C]]
; CHECK-NEXT: ret float [[D]]
;
%C = fmul fast float %A, %B
@@ -169,7 +169,7 @@ define float @select_nnan_fsub_swapped(i1 %cond, float %A, float %B) {
define float @select_nnan_fsub_fast_math(i1 %cond, float %A, float %B) {
; CHECK-LABEL: @select_nnan_fsub_fast_math(
; CHECK-NEXT: [[C:%.*]] = select nnan i1 [[COND:%.*]], float [[B:%.*]], float 0.000000e+00
-; CHECK-NEXT: [[D:%.*]] = fsub fast float [[A:%.*]], [[C]]
+; CHECK-NEXT: [[D:%.*]] = fsub nnan float [[A:%.*]], [[C]]
; CHECK-NEXT: ret float [[D]]
;
%C = fsub fast float %A, %B
@@ -180,7 +180,7 @@ define float @select_nnan_fsub_fast_math(i1 %cond, float %A, float %B) {
define float @select_nnan_fsub_swapped_fast_math(i1 %cond, float %A, float %B) {
; CHECK-LABEL: @select_nnan_fsub_swapped_fast_math(
; CHECK-NEXT: [[C:%.*]] = select nnan i1 [[COND:%.*]], float 0.000000e+00, float [[B:%.*]]
-; CHECK-NEXT: [[D:%.*]] = fsub fast float [[A:%.*]], [[C]]
+; CHECK-NEXT: [[D:%.*]] = fsub nnan float [[A:%.*]], [[C]]
; CHECK-NEXT: ret float [[D]]
;
%C = fsub fast float %A, %B
@@ -247,7 +247,7 @@ define float @select_nnan_fdiv_swapped(i1 %cond, float %A, float %B) {
define float @select_nnan_fdiv_fast_math(i1 %cond, float %A, float %B) {
; CHECK-LABEL: @select_nnan_fdiv_fast_math(
; CHECK-NEXT: [[C:%.*]] = select nnan i1 [[COND:%.*]], float [[B:%.*]], float 1.000000e+00
-; CHECK-NEXT: [[D:%.*]] = fdiv fast float [[A:%.*]], [[C]]
+; CHECK-NEXT: [[D:%.*]] = fdiv nnan float [[A:%.*]], [[C]]
; CHECK-NEXT: ret float [[D]]
;
%C = fdiv fast float %A, %B
@@ -258,7 +258,7 @@ define float @select_nnan_fdiv_fast_math(i1 %cond, float %A, float %B) {
define float @select_nnan_fdiv_swapped_fast_math(i1 %cond, float %A, float %B) {
; CHECK-LABEL: @select_nnan_fdiv_swapped_fast_math(
; CHECK-NEXT: [[C:%.*]] = select nnan i1 [[COND:%.*]], float 1.000000e+00, float [[B:%.*]]
-; CHECK-NEXT: [[D:%.*]] = fdiv fast float [[A:%.*]], [[C]]
+; CHECK-NEXT: [[D:%.*]] = fdiv nnan float [[A:%.*]], [[C]]
; CHECK-NEXT: ret float [[D]]
;
%C = fdiv fast float %A, %B
More information about the llvm-commits
mailing list