[llvm] [InstCombine] Fold `fptrunc(x) ord/uno [ C | fptrunc(y) ]` to `x ord/uno [ C | y ]` (PR #185844)
Kunqiu Chen via llvm-commits
llvm-commits at lists.llvm.org
Mon Apr 13 07:59:19 PDT 2026
https://github.com/Camsyn updated https://github.com/llvm/llvm-project/pull/185844
>From 0c191e8ca46da97c8b105076e7dcc81b5839f1c0 Mon Sep 17 00:00:00 2001
From: Camsyn <camsyn at foxmail.com>
Date: Wed, 11 Mar 2026 16:39:38 +0800
Subject: [PATCH 1/5] Before-commit test
---
.../Transforms/InstCombine/fold-fcmp-trunc.ll | 54 ++++++++++++++++++-
1 file changed, 53 insertions(+), 1 deletion(-)
diff --git a/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll b/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
index 371f9b6807fe4..2199db6c984f3 100644
--- a/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
+++ b/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
@@ -57,6 +57,58 @@ define i1 @fcmp_trunc_zero(double %0) {
ret i1 %result
}
+define i1 @fcmp_trunc_uno(double %0) {
+; CHECK-LABEL: define i1 @fcmp_trunc_uno(
+; CHECK-SAME: double [[TMP0:%.*]]) {
+; CHECK-NEXT: [[TRUNC:%.*]] = fptrunc double [[TMP0]] to float
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp uno float [[TRUNC]], 0.000000e+00
+; CHECK-NEXT: ret i1 [[RESULT]]
+;
+ %trunc = fptrunc double %0 to float
+ %result = fcmp uno float %trunc, 0.000000e+00
+ ret i1 %result
+}
+
+define i1 @fcmp_trunc_ord_inf(double %0) {
+; CHECK-LABEL: define i1 @fcmp_trunc_ord_inf(
+; CHECK-SAME: double [[TMP0:%.*]]) {
+; CHECK-NEXT: [[TRUNC:%.*]] = fptrunc double [[TMP0]] to float
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp ord float [[TRUNC]], 0.000000e+00
+; CHECK-NEXT: ret i1 [[RESULT]]
+;
+ %trunc = fptrunc double %0 to float
+ %result = fcmp ord float %trunc, 0x7FF0000000000000
+ ret i1 %result
+}
+
+define i1 @fcmp_trunc_pair_uno(double %x, double %y) {
+; CHECK-LABEL: define i1 @fcmp_trunc_pair_uno(
+; CHECK-SAME: double [[X:%.*]], double [[Y:%.*]]) {
+; CHECK-NEXT: [[TX:%.*]] = fptrunc double [[X]] to float
+; CHECK-NEXT: [[TY:%.*]] = fptrunc double [[Y]] to float
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp uno float [[TX]], [[TY]]
+; CHECK-NEXT: ret i1 [[RESULT]]
+;
+ %tx = fptrunc double %x to float
+ %ty = fptrunc double %y to float
+ %result = fcmp uno float %tx, %ty
+ ret i1 %result
+}
+
+define i1 @fcmp_trunc_pair_ord(double %x, double %y) {
+; CHECK-LABEL: define i1 @fcmp_trunc_pair_ord(
+; CHECK-SAME: double [[X:%.*]], double [[Y:%.*]]) {
+; CHECK-NEXT: [[TX:%.*]] = fptrunc double [[X]] to float
+; CHECK-NEXT: [[TY:%.*]] = fptrunc double [[Y]] to float
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp ord float [[TX]], [[TY]]
+; CHECK-NEXT: ret i1 [[RESULT]]
+;
+ %tx = fptrunc double %x to float
+ %ty = fptrunc double %y to float
+ %result = fcmp ord float %tx, %ty
+ ret i1 %result
+}
+
define i1 @fcmp_trunc_with_nnan(double %0) {
; CHECK-LABEL: define i1 @fcmp_trunc_with_nnan(
; CHECK-SAME: double [[TMP0:%.*]]) {
@@ -104,7 +156,7 @@ define i1 @fcmp_trunc_with_reassoc(double %0) {
define i1 @fcmp_trunc_with_fast(double %0) {
; CHECK-LABEL: define i1 @fcmp_trunc_with_fast(
; CHECK-SAME: double [[TMP0:%.*]]) {
-; CHECK-NEXT: [[RESULT:%.*]] = fcmp fast oge double [[TMP0]], 0x4058FFFFF0000000
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp fast oge double [[TMP0]], 0x4058FFFFF0000000
; CHECK-NEXT: ret i1 [[RESULT]]
;
%trunc = fptrunc double %0 to float
>From b4dd5f54188ded489c22a847b20577664d6b4316 Mon Sep 17 00:00:00 2001
From: Camsyn <camsyn at foxmail.com>
Date: Wed, 11 Mar 2026 17:36:18 +0800
Subject: [PATCH 2/5] Fix #185698
---
.../InstCombine/InstCombineCompares.cpp | 59 +++++++++++++------
1 file changed, 42 insertions(+), 17 deletions(-)
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 7f1ced9505b9b..15ff2eb24600c 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -8290,15 +8290,43 @@ static Instruction *foldFCmpReciprocalAndZero(FCmpInst &I, Instruction *LHSI,
// Transform 'fptrunc(x) cmp C' to 'x cmp ext(C)' if possible.
// Patterns include:
-// fptrunc(x) < C --> x < ext(C)
-// fptrunc(x) <= C --> x <= ext(C)
-// fptrunc(x) > C --> x > ext(C)
-// fptrunc(x) >= C --> x >= ext(C)
+// fptrunc(x) < C --> x < ext(C)
+// fptrunc(x) <= C --> x <= ext(C)
+// fptrunc(x) > C --> x > ext(C)
+// fptrunc(x) >= C --> x >= ext(C)
+// fptrunc(x) ord/uno C --> x ord/uno 0
+// fptrunc(x) ord/uno fptrunc(y) --> x ord/uno y
// where 'ext(C)' is the extension of 'C' to the type of 'x' with a small bias
// due to precision loss.
static Instruction *foldFCmpFpTrunc(FCmpInst &I, const Instruction &FPTrunc,
- const Constant &C) {
+ const Value &CmpRHS) {
FCmpInst::Predicate Pred = I.getPredicate();
+ Type *DestType = FPTrunc.getOperand(0)->getType();
+
+ // Handle ord/uno [C | fptrunc(y)]
+ if (Pred == FCmpInst::FCMP_ORD || Pred == FCmpInst::FCMP_UNO) {
+ Value *RHS;
+ const APFloat *CValue;
+ if (match(&CmpRHS, m_FPTrunc(m_Value(RHS)))) {
+ if (DestType != RHS->getType())
+ return nullptr;
+ } else if (match(&CmpRHS, m_APFloat(CValue))) {
+ assert(!CValue->isNaN() &&
+ "NaN RHS should be folded away by simplifyFCmpInst()");
+ RHS = ConstantFP::getZero(DestType);
+ } else {
+ return nullptr;
+ }
+
+ return new FCmpInst(Pred, FPTrunc.getOperand(0), RHS, "", &I);
+ }
+
+ // Handle <, >, <=, >=
+ const APFloat *CValue;
+ // TODO: support vec
+ if (!match(&CmpRHS, m_APFloat(CValue)))
+ return nullptr;
+
bool RoundDown = false;
if (Pred == FCmpInst::FCMP_OGE || Pred == FCmpInst::FCMP_UGE ||
@@ -8310,10 +8338,6 @@ static Instruction *foldFCmpFpTrunc(FCmpInst &I, const Instruction &FPTrunc,
else
return nullptr;
- const APFloat *CValue;
- if (!match(&C, m_APFloat(CValue)))
- return nullptr;
-
if (CValue->isNaN() || CValue->isInfinity())
return nullptr;
@@ -8332,7 +8356,6 @@ static Instruction *foldFCmpFpTrunc(FCmpInst &I, const Instruction &FPTrunc,
APFloat NextCValue = NextValue(*CValue, RoundDown);
- Type *DestType = FPTrunc.getOperand(0)->getType();
const fltSemantics &DestFltSema =
DestType->getScalarType()->getFltSemantics();
@@ -8354,7 +8377,7 @@ static Instruction *foldFCmpFpTrunc(FCmpInst &I, const Instruction &FPTrunc,
scalbn(ExtCValue + ExtNextCValue, -1, APFloat::rmNearestTiesToEven);
const fltSemantics &SrcFltSema =
- C.getType()->getScalarType()->getFltSemantics();
+ CmpRHS.getType()->getScalarType()->getFltSemantics();
// 'MidValue' might be rounded to 'NextCValue'. Correct it here.
APFloat MidValue = ConvertFltSema(ExtMidValue, SrcFltSema);
@@ -8835,10 +8858,16 @@ Instruction *InstCombinerImpl::visitFCmpInst(FCmpInst &I) {
}
}
- // Handle fcmp with instruction LHS and constant RHS.
Instruction *LHSI;
+ // Handle fcmp with fptrunc LHS
+ if (match(Op0, m_Instruction(LHSI)) &&
+ LHSI->getOpcode() == Instruction::FPTrunc)
+ if (Instruction *NV = foldFCmpFpTrunc(I, *LHSI, *Op1))
+ return NV;
+
+ // Handle fcmp with instruction LHS and constant RHS.
Constant *RHSC;
- if (match(Op0, m_Instruction(LHSI)) && match(Op1, m_Constant(RHSC))) {
+ if (LHSI && match(Op1, m_Constant(RHSC))) {
switch (LHSI->getOpcode()) {
case Instruction::Select:
// fcmp eq (cond ? x : -x), 0 --> fcmp eq x, 0
@@ -8872,10 +8901,6 @@ Instruction *InstCombinerImpl::visitFCmpInst(FCmpInst &I) {
foldCmpLoadFromIndexedGlobal(cast<LoadInst>(LHSI), GEP, I))
return Res;
break;
- case Instruction::FPTrunc:
- if (Instruction *NV = foldFCmpFpTrunc(I, *LHSI, *RHSC))
- return NV;
- break;
}
}
>From a75e8c731e3aaed542e5ceddafb6af6905f7581c Mon Sep 17 00:00:00 2001
From: Camsyn <camsyn at foxmail.com>
Date: Wed, 11 Mar 2026 18:08:23 +0800
Subject: [PATCH 3/5] After-commit test
---
.../Transforms/InstCombine/fold-fcmp-trunc.ll | 18 +++++-------------
.../Transforms/InstCombine/known-never-nan.ll | 3 +--
2 files changed, 6 insertions(+), 15 deletions(-)
diff --git a/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll b/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
index 2199db6c984f3..e65e31700240f 100644
--- a/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
+++ b/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
@@ -60,8 +60,7 @@ define i1 @fcmp_trunc_zero(double %0) {
define i1 @fcmp_trunc_uno(double %0) {
; CHECK-LABEL: define i1 @fcmp_trunc_uno(
; CHECK-SAME: double [[TMP0:%.*]]) {
-; CHECK-NEXT: [[TRUNC:%.*]] = fptrunc double [[TMP0]] to float
-; CHECK-NEXT: [[RESULT:%.*]] = fcmp uno float [[TRUNC]], 0.000000e+00
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp uno double [[TMP0]], 0.000000e+00
; CHECK-NEXT: ret i1 [[RESULT]]
;
%trunc = fptrunc double %0 to float
@@ -72,8 +71,7 @@ define i1 @fcmp_trunc_uno(double %0) {
define i1 @fcmp_trunc_ord_inf(double %0) {
; CHECK-LABEL: define i1 @fcmp_trunc_ord_inf(
; CHECK-SAME: double [[TMP0:%.*]]) {
-; CHECK-NEXT: [[TRUNC:%.*]] = fptrunc double [[TMP0]] to float
-; CHECK-NEXT: [[RESULT:%.*]] = fcmp ord float [[TRUNC]], 0.000000e+00
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp ord double [[TMP0]], 0.000000e+00
; CHECK-NEXT: ret i1 [[RESULT]]
;
%trunc = fptrunc double %0 to float
@@ -84,9 +82,7 @@ define i1 @fcmp_trunc_ord_inf(double %0) {
define i1 @fcmp_trunc_pair_uno(double %x, double %y) {
; CHECK-LABEL: define i1 @fcmp_trunc_pair_uno(
; CHECK-SAME: double [[X:%.*]], double [[Y:%.*]]) {
-; CHECK-NEXT: [[TX:%.*]] = fptrunc double [[X]] to float
-; CHECK-NEXT: [[TY:%.*]] = fptrunc double [[Y]] to float
-; CHECK-NEXT: [[RESULT:%.*]] = fcmp uno float [[TX]], [[TY]]
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp uno double [[X]], [[Y]]
; CHECK-NEXT: ret i1 [[RESULT]]
;
%tx = fptrunc double %x to float
@@ -98,9 +94,7 @@ define i1 @fcmp_trunc_pair_uno(double %x, double %y) {
define i1 @fcmp_trunc_pair_ord(double %x, double %y) {
; CHECK-LABEL: define i1 @fcmp_trunc_pair_ord(
; CHECK-SAME: double [[X:%.*]], double [[Y:%.*]]) {
-; CHECK-NEXT: [[TX:%.*]] = fptrunc double [[X]] to float
-; CHECK-NEXT: [[TY:%.*]] = fptrunc double [[Y]] to float
-; CHECK-NEXT: [[RESULT:%.*]] = fcmp ord float [[TX]], [[TY]]
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp ord double [[X]], [[Y]]
; CHECK-NEXT: ret i1 [[RESULT]]
;
%tx = fptrunc double %x to float
@@ -379,8 +373,7 @@ define i1 @fcmp_trunc_literal_positive_inf(double %0) {
define i1 @fcmp_trunc_literal_negative_inf(double %0) {
; CHECK-LABEL: define i1 @fcmp_trunc_literal_negative_inf(
; CHECK-SAME: double [[TMP0:%.*]]) {
-; CHECK-NEXT: [[TRUNC:%.*]] = fptrunc double [[TMP0]] to float
-; CHECK-NEXT: [[RESULT:%.*]] = fcmp uno float [[TRUNC]], 0.000000e+00
+; CHECK-NEXT: [[RESULT:%.*]] = fcmp uno double [[TMP0]], 0.000000e+00
; CHECK-NEXT: ret i1 [[RESULT]]
;
%trunc = fptrunc double %0 to float
@@ -723,4 +716,3 @@ define i1 @fcmp_trunc_mn_ppc_fp128(ppc_fp128 %0) {
%result = fcmp uge float %trunc, 0xC7EFFFFF00000000
ret i1 %result
}
-
diff --git a/llvm/test/Transforms/InstCombine/known-never-nan.ll b/llvm/test/Transforms/InstCombine/known-never-nan.ll
index c4ce874029647..759cabae3d72f 100644
--- a/llvm/test/Transforms/InstCombine/known-never-nan.ll
+++ b/llvm/test/Transforms/InstCombine/known-never-nan.ll
@@ -150,8 +150,7 @@ define i1 @fpext_maybe_nan(float %arg0) {
define i1 @fptrunc_maybe_nan(double %arg0) {
; CHECK-LABEL: @fptrunc_maybe_nan(
-; CHECK-NEXT: [[OP:%.*]] = fptrunc double [[ARG0:%.*]] to float
-; CHECK-NEXT: [[TMP:%.*]] = fcmp ord float [[OP]], 0.000000e+00
+; CHECK-NEXT: [[TMP:%.*]] = fcmp ord double [[ARG0:%.*]], 0.000000e+00
; CHECK-NEXT: ret i1 [[TMP]]
;
%op = fptrunc double %arg0 to float
>From 1ec82b7e85c97861de51f14d3c0df7efa3ad60bc Mon Sep 17 00:00:00 2001
From: Camsyn <camsyn at foxmail.com>
Date: Mon, 13 Apr 2026 22:56:29 +0800
Subject: [PATCH 4/5] Follow the review comments
---
.../InstCombine/InstCombineCompares.cpp | 56 +++++++++----------
.../Transforms/InstCombine/fold-fcmp-trunc.ll | 1 +
2 files changed, 26 insertions(+), 31 deletions(-)
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 15ff2eb24600c..8d283c39dfd53 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -26,6 +26,7 @@
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/InstrTypes.h"
+#include "llvm/IR/Instruction.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/PatternMatch.h"
@@ -8295,38 +8296,27 @@ static Instruction *foldFCmpReciprocalAndZero(FCmpInst &I, Instruction *LHSI,
// fptrunc(x) > C --> x > ext(C)
// fptrunc(x) >= C --> x >= ext(C)
// fptrunc(x) ord/uno C --> x ord/uno 0
-// fptrunc(x) ord/uno fptrunc(y) --> x ord/uno y
// where 'ext(C)' is the extension of 'C' to the type of 'x' with a small bias
// due to precision loss.
static Instruction *foldFCmpFpTrunc(FCmpInst &I, const Instruction &FPTrunc,
- const Value &CmpRHS) {
+ const Constant &C) {
FCmpInst::Predicate Pred = I.getPredicate();
Type *DestType = FPTrunc.getOperand(0)->getType();
- // Handle ord/uno [C | fptrunc(y)]
- if (Pred == FCmpInst::FCMP_ORD || Pred == FCmpInst::FCMP_UNO) {
- Value *RHS;
- const APFloat *CValue;
- if (match(&CmpRHS, m_FPTrunc(m_Value(RHS)))) {
- if (DestType != RHS->getType())
- return nullptr;
- } else if (match(&CmpRHS, m_APFloat(CValue))) {
- assert(!CValue->isNaN() &&
- "NaN RHS should be folded away by simplifyFCmpInst()");
- RHS = ConstantFP::getZero(DestType);
- } else {
- return nullptr;
- }
-
- return new FCmpInst(Pred, FPTrunc.getOperand(0), RHS, "", &I);
- }
-
- // Handle <, >, <=, >=
const APFloat *CValue;
// TODO: support vec
- if (!match(&CmpRHS, m_APFloat(CValue)))
+ if (!match(&C, m_APFloat(CValue)))
return nullptr;
+ // Handle ord/uno
+ if (Pred == FCmpInst::FCMP_ORD || Pred == FCmpInst::FCMP_UNO) {
+ assert(!CValue->isNaN() &&
+ "X ord/uno NaN should be folded away by simplifyFCmpInst()");
+ return new FCmpInst(Pred, FPTrunc.getOperand(0),
+ ConstantFP::getZero(DestType), "", &I);
+ }
+
+ // Handle <, >, <=, >=
bool RoundDown = false;
if (Pred == FCmpInst::FCMP_OGE || Pred == FCmpInst::FCMP_UGE ||
@@ -8377,7 +8367,7 @@ static Instruction *foldFCmpFpTrunc(FCmpInst &I, const Instruction &FPTrunc,
scalbn(ExtCValue + ExtNextCValue, -1, APFloat::rmNearestTiesToEven);
const fltSemantics &SrcFltSema =
- CmpRHS.getType()->getScalarType()->getFltSemantics();
+ C.getType()->getScalarType()->getFltSemantics();
// 'MidValue' might be rounded to 'NextCValue'. Correct it here.
APFloat MidValue = ConvertFltSema(ExtMidValue, SrcFltSema);
@@ -8858,16 +8848,10 @@ Instruction *InstCombinerImpl::visitFCmpInst(FCmpInst &I) {
}
}
- Instruction *LHSI;
- // Handle fcmp with fptrunc LHS
- if (match(Op0, m_Instruction(LHSI)) &&
- LHSI->getOpcode() == Instruction::FPTrunc)
- if (Instruction *NV = foldFCmpFpTrunc(I, *LHSI, *Op1))
- return NV;
-
// Handle fcmp with instruction LHS and constant RHS.
+ Instruction *LHSI;
Constant *RHSC;
- if (LHSI && match(Op1, m_Constant(RHSC))) {
+ if (match(Op0, m_Instruction(LHSI)) && match(Op1, m_Constant(RHSC))) {
switch (LHSI->getOpcode()) {
case Instruction::Select:
// fcmp eq (cond ? x : -x), 0 --> fcmp eq x, 0
@@ -8901,6 +8885,10 @@ Instruction *InstCombinerImpl::visitFCmpInst(FCmpInst &I) {
foldCmpLoadFromIndexedGlobal(cast<LoadInst>(LHSI), GEP, I))
return Res;
break;
+ case Instruction::FPTrunc:
+ if (Instruction *NV = foldFCmpFpTrunc(I, *LHSI, *RHSC))
+ return NV;
+ break;
}
}
@@ -8929,6 +8917,12 @@ Instruction *InstCombinerImpl::visitFCmpInst(FCmpInst &I) {
if (match(Op1, m_FAdd(m_Value(Y), m_AnyZeroFP())))
return new FCmpInst(Pred, Op0, Y, "", &I);
+ // fcmp ord/uno (fptrunc X), (fptrunc Y) -> fcmp ord/uno X, Y
+ if ((Pred == FCmpInst::FCMP_ORD || Pred == FCmpInst::FCMP_UNO) &&
+ match(Op0, m_Trunc(m_Value(X))) && match(Op0, m_Trunc(m_Value(Y))) &&
+ X->getType() == Y->getType())
+ return new FCmpInst(Pred, X, Y, "", &I);
+
if (match(Op0, m_FPExt(m_Value(X)))) {
// fcmp (fpext X), (fpext Y) -> fcmp X, Y
if (match(Op1, m_FPExt(m_Value(Y))) && X->getType() == Y->getType())
diff --git a/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll b/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
index e65e31700240f..d42ba952ace99 100644
--- a/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
+++ b/llvm/test/Transforms/InstCombine/fold-fcmp-trunc.ll
@@ -716,3 +716,4 @@ define i1 @fcmp_trunc_mn_ppc_fp128(ppc_fp128 %0) {
%result = fcmp uge float %trunc, 0xC7EFFFFF00000000
ret i1 %result
}
+
>From 2efbf3050a1d9b8aa0cba245625520683877915e Mon Sep 17 00:00:00 2001
From: Camsyn <camsyn at foxmail.com>
Date: Mon, 13 Apr 2026 22:59:00 +0800
Subject: [PATCH 5/5] Adjust comments
---
.../lib/Transforms/InstCombine/InstCombineCompares.cpp | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
index 8d283c39dfd53..0a6e7d7bdf9c3 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCompares.cpp
@@ -8291,11 +8291,11 @@ static Instruction *foldFCmpReciprocalAndZero(FCmpInst &I, Instruction *LHSI,
// Transform 'fptrunc(x) cmp C' to 'x cmp ext(C)' if possible.
// Patterns include:
-// fptrunc(x) < C --> x < ext(C)
-// fptrunc(x) <= C --> x <= ext(C)
-// fptrunc(x) > C --> x > ext(C)
-// fptrunc(x) >= C --> x >= ext(C)
-// fptrunc(x) ord/uno C --> x ord/uno 0
+// fptrunc(x) < C --> x < ext(C)
+// fptrunc(x) <= C --> x <= ext(C)
+// fptrunc(x) > C --> x > ext(C)
+// fptrunc(x) >= C --> x >= ext(C)
+// fptrunc(x) ord/uno C --> x ord/uno 0
// where 'ext(C)' is the extension of 'C' to the type of 'x' with a small bias
// due to precision loss.
static Instruction *foldFCmpFpTrunc(FCmpInst &I, const Instruction &FPTrunc,
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