[clang] [ARM] Fix NaN behaviour for MVE compare intrinsics (PR #116371)
Oliver Stannard via cfe-commits
cfe-commits at lists.llvm.org
Fri Nov 15 02:22:09 PST 2024
https://github.com/ostannard created https://github.com/llvm/llvm-project/pull/116371
The MVE intrinsics are defined as having the same behaviour as the instructions which they correspond to. In particular, the vcmpleq and vcmpltq intrinsics correspond to the VCMP instruction with the LE or LT condition. However, these instructions with these two conditions do not match the normal IEEE754 behaviour for NaNs, they return true if either operand is a NaN, instead of false. Therefore we need to generate `fcmp` IR instructions with the `ule` and `ult` conditions, instead of `ole` and `olt`.
This differs from AdvSIMD, where only instructions with the EQ, GE and GT conditions are available, and the intrinsics for the others are defined by swapping the condition and operand order, so the results match the IEEE754 behaviour for NaNs.
>From 6bfe667f87da2551e7080af3caede272378e1e4d Mon Sep 17 00:00:00 2001
From: Oliver Stannard <oliver.stannard at arm.com>
Date: Thu, 14 Nov 2024 18:16:12 +0000
Subject: [PATCH] [ARM] Fix NaN behaviour for MVE compare intrinsics
The MVE intrinsics are defined as having the same behaviour as the
instructions which they correspond to. In particular, the vcmpleq and
vcmpltq intrinsics correspond to the VCMP instruction with the LE or LT
condition. However, these instructions with these two conditions do not
match the normal IEEE754 behaviour for NaNs, they return true if either
operand is a NaN, instead of false. Therefore we need to generate `fcmp`
IR instructions with the `ule` and `ult` conditions, instead of `ole`
and `olt`.
This differs from AdvSIMD, where only instructions with the EQ, GE and
GT conditions are available, and the intrinsics for the others are
defined by swapping the condition and operand order, so the results
match the IEEE754 behaviour for NaNs.
---
clang/include/clang/Basic/arm_mve.td | 4 +--
clang/include/clang/Basic/arm_mve_defs.td | 2 ++
.../test/CodeGen/arm-mve-intrinsics/compare.c | 32 +++++++++----------
3 files changed, 20 insertions(+), 18 deletions(-)
diff --git a/clang/include/clang/Basic/arm_mve.td b/clang/include/clang/Basic/arm_mve.td
index 1debb94a0a7b81..93abbc47c54dd5 100644
--- a/clang/include/clang/Basic/arm_mve.td
+++ b/clang/include/clang/Basic/arm_mve.td
@@ -753,8 +753,8 @@ let params = T.Float in {
defm: compare<"ne", fcmp_ne>;
defm: compare<"gt", fcmp_gt>;
defm: compare<"ge", fcmp_ge>;
- defm: compare<"lt", fcmp_lt>;
- defm: compare<"le", fcmp_le>;
+ defm: compare<"lt", fcmp_ult>;
+ defm: compare<"le", fcmp_ule>;
}
let params = T.Signed in {
diff --git a/clang/include/clang/Basic/arm_mve_defs.td b/clang/include/clang/Basic/arm_mve_defs.td
index 1a090c08cc8531..9c725c890e7e4d 100644
--- a/clang/include/clang/Basic/arm_mve_defs.td
+++ b/clang/include/clang/Basic/arm_mve_defs.td
@@ -118,6 +118,8 @@ def fcmp_gt: IRBuilder<"CreateFCmpOGT">;
def fcmp_ge: IRBuilder<"CreateFCmpOGE">;
def fcmp_lt: IRBuilder<"CreateFCmpOLT">;
def fcmp_le: IRBuilder<"CreateFCmpOLE">;
+def fcmp_ult: IRBuilder<"CreateFCmpULT">;
+def fcmp_ule: IRBuilder<"CreateFCmpULE">;
def splat: CGHelperFn<"ARMMVEVectorSplat">;
def select: IRBuilder<"CreateSelect">;
def fneg: IRBuilder<"CreateFNeg">;
diff --git a/clang/test/CodeGen/arm-mve-intrinsics/compare.c b/clang/test/CodeGen/arm-mve-intrinsics/compare.c
index 8f190990a65869..8886cf5c100581 100644
--- a/clang/test/CodeGen/arm-mve-intrinsics/compare.c
+++ b/clang/test/CodeGen/arm-mve-intrinsics/compare.c
@@ -2376,7 +2376,7 @@ mve_pred16_t test_vcmphiq_m_n_u32(uint32x4_t a, uint32_t b, mve_pred16_t p)
// CHECK-LABEL: @test_vcmpleq_f16(
// CHECK-NEXT: entry:
-// CHECK-NEXT: [[TMP0:%.*]] = fcmp ole <8 x half> [[A:%.*]], [[B:%.*]]
+// CHECK-NEXT: [[TMP0:%.*]] = fcmp ule <8 x half> [[A:%.*]], [[B:%.*]]
// CHECK-NEXT: [[TMP1:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v8i1(<8 x i1> [[TMP0]])
// CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
// CHECK-NEXT: ret i16 [[TMP2]]
@@ -2392,7 +2392,7 @@ mve_pred16_t test_vcmpleq_f16(float16x8_t a, float16x8_t b)
// CHECK-LABEL: @test_vcmpleq_f32(
// CHECK-NEXT: entry:
-// CHECK-NEXT: [[TMP0:%.*]] = fcmp ole <4 x float> [[A:%.*]], [[B:%.*]]
+// CHECK-NEXT: [[TMP0:%.*]] = fcmp ule <4 x float> [[A:%.*]], [[B:%.*]]
// CHECK-NEXT: [[TMP1:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v4i1(<4 x i1> [[TMP0]])
// CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
// CHECK-NEXT: ret i16 [[TMP2]]
@@ -2458,7 +2458,7 @@ mve_pred16_t test_vcmpleq_s32(int32x4_t a, int32x4_t b)
// CHECK-NEXT: entry:
// CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement <8 x half> poison, half [[B:%.*]], i64 0
// CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector <8 x half> [[DOTSPLATINSERT]], <8 x half> poison, <8 x i32> zeroinitializer
-// CHECK-NEXT: [[TMP0:%.*]] = fcmp ole <8 x half> [[A:%.*]], [[DOTSPLAT]]
+// CHECK-NEXT: [[TMP0:%.*]] = fcmp ule <8 x half> [[A:%.*]], [[DOTSPLAT]]
// CHECK-NEXT: [[TMP1:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v8i1(<8 x i1> [[TMP0]])
// CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
// CHECK-NEXT: ret i16 [[TMP2]]
@@ -2476,7 +2476,7 @@ mve_pred16_t test_vcmpleq_n_f16(float16x8_t a, float16_t b)
// CHECK-NEXT: entry:
// CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement <4 x float> poison, float [[B:%.*]], i64 0
// CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector <4 x float> [[DOTSPLATINSERT]], <4 x float> poison, <4 x i32> zeroinitializer
-// CHECK-NEXT: [[TMP0:%.*]] = fcmp ole <4 x float> [[A:%.*]], [[DOTSPLAT]]
+// CHECK-NEXT: [[TMP0:%.*]] = fcmp ule <4 x float> [[A:%.*]], [[DOTSPLAT]]
// CHECK-NEXT: [[TMP1:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v4i1(<4 x i1> [[TMP0]])
// CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
// CHECK-NEXT: ret i16 [[TMP2]]
@@ -2548,7 +2548,7 @@ mve_pred16_t test_vcmpleq_n_s32(int32x4_t a, int32_t b)
// CHECK-NEXT: entry:
// CHECK-NEXT: [[TMP0:%.*]] = zext i16 [[P:%.*]] to i32
// CHECK-NEXT: [[TMP1:%.*]] = call <8 x i1> @llvm.arm.mve.pred.i2v.v8i1(i32 [[TMP0]])
-// CHECK-NEXT: [[TMP2:%.*]] = fcmp ole <8 x half> [[A:%.*]], [[B:%.*]]
+// CHECK-NEXT: [[TMP2:%.*]] = fcmp ule <8 x half> [[A:%.*]], [[B:%.*]]
// CHECK-NEXT: [[TMP3:%.*]] = and <8 x i1> [[TMP1]], [[TMP2]]
// CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v8i1(<8 x i1> [[TMP3]])
// CHECK-NEXT: [[TMP5:%.*]] = trunc i32 [[TMP4]] to i16
@@ -2567,7 +2567,7 @@ mve_pred16_t test_vcmpleq_m_f16(float16x8_t a, float16x8_t b, mve_pred16_t p)
// CHECK-NEXT: entry:
// CHECK-NEXT: [[TMP0:%.*]] = zext i16 [[P:%.*]] to i32
// CHECK-NEXT: [[TMP1:%.*]] = call <4 x i1> @llvm.arm.mve.pred.i2v.v4i1(i32 [[TMP0]])
-// CHECK-NEXT: [[TMP2:%.*]] = fcmp ole <4 x float> [[A:%.*]], [[B:%.*]]
+// CHECK-NEXT: [[TMP2:%.*]] = fcmp ule <4 x float> [[A:%.*]], [[B:%.*]]
// CHECK-NEXT: [[TMP3:%.*]] = and <4 x i1> [[TMP1]], [[TMP2]]
// CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v4i1(<4 x i1> [[TMP3]])
// CHECK-NEXT: [[TMP5:%.*]] = trunc i32 [[TMP4]] to i16
@@ -2645,7 +2645,7 @@ mve_pred16_t test_vcmpleq_m_s32(int32x4_t a, int32x4_t b, mve_pred16_t p)
// CHECK-NEXT: [[TMP1:%.*]] = call <8 x i1> @llvm.arm.mve.pred.i2v.v8i1(i32 [[TMP0]])
// CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement <8 x half> poison, half [[B:%.*]], i64 0
// CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector <8 x half> [[DOTSPLATINSERT]], <8 x half> poison, <8 x i32> zeroinitializer
-// CHECK-NEXT: [[TMP2:%.*]] = fcmp ole <8 x half> [[A:%.*]], [[DOTSPLAT]]
+// CHECK-NEXT: [[TMP2:%.*]] = fcmp ule <8 x half> [[A:%.*]], [[DOTSPLAT]]
// CHECK-NEXT: [[TMP3:%.*]] = and <8 x i1> [[TMP1]], [[TMP2]]
// CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v8i1(<8 x i1> [[TMP3]])
// CHECK-NEXT: [[TMP5:%.*]] = trunc i32 [[TMP4]] to i16
@@ -2666,7 +2666,7 @@ mve_pred16_t test_vcmpleq_m_n_f16(float16x8_t a, float16_t b, mve_pred16_t p)
// CHECK-NEXT: [[TMP1:%.*]] = call <4 x i1> @llvm.arm.mve.pred.i2v.v4i1(i32 [[TMP0]])
// CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement <4 x float> poison, float [[B:%.*]], i64 0
// CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector <4 x float> [[DOTSPLATINSERT]], <4 x float> poison, <4 x i32> zeroinitializer
-// CHECK-NEXT: [[TMP2:%.*]] = fcmp ole <4 x float> [[A:%.*]], [[DOTSPLAT]]
+// CHECK-NEXT: [[TMP2:%.*]] = fcmp ule <4 x float> [[A:%.*]], [[DOTSPLAT]]
// CHECK-NEXT: [[TMP3:%.*]] = and <4 x i1> [[TMP1]], [[TMP2]]
// CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v4i1(<4 x i1> [[TMP3]])
// CHECK-NEXT: [[TMP5:%.*]] = trunc i32 [[TMP4]] to i16
@@ -2746,7 +2746,7 @@ mve_pred16_t test_vcmpleq_m_n_s32(int32x4_t a, int32_t b, mve_pred16_t p)
// CHECK-LABEL: @test_vcmpltq_f16(
// CHECK-NEXT: entry:
-// CHECK-NEXT: [[TMP0:%.*]] = fcmp olt <8 x half> [[A:%.*]], [[B:%.*]]
+// CHECK-NEXT: [[TMP0:%.*]] = fcmp ult <8 x half> [[A:%.*]], [[B:%.*]]
// CHECK-NEXT: [[TMP1:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v8i1(<8 x i1> [[TMP0]])
// CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
// CHECK-NEXT: ret i16 [[TMP2]]
@@ -2762,7 +2762,7 @@ mve_pred16_t test_vcmpltq_f16(float16x8_t a, float16x8_t b)
// CHECK-LABEL: @test_vcmpltq_f32(
// CHECK-NEXT: entry:
-// CHECK-NEXT: [[TMP0:%.*]] = fcmp olt <4 x float> [[A:%.*]], [[B:%.*]]
+// CHECK-NEXT: [[TMP0:%.*]] = fcmp ult <4 x float> [[A:%.*]], [[B:%.*]]
// CHECK-NEXT: [[TMP1:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v4i1(<4 x i1> [[TMP0]])
// CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
// CHECK-NEXT: ret i16 [[TMP2]]
@@ -2828,7 +2828,7 @@ mve_pred16_t test_vcmpltq_s32(int32x4_t a, int32x4_t b)
// CHECK-NEXT: entry:
// CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement <8 x half> poison, half [[B:%.*]], i64 0
// CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector <8 x half> [[DOTSPLATINSERT]], <8 x half> poison, <8 x i32> zeroinitializer
-// CHECK-NEXT: [[TMP0:%.*]] = fcmp olt <8 x half> [[A:%.*]], [[DOTSPLAT]]
+// CHECK-NEXT: [[TMP0:%.*]] = fcmp ult <8 x half> [[A:%.*]], [[DOTSPLAT]]
// CHECK-NEXT: [[TMP1:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v8i1(<8 x i1> [[TMP0]])
// CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
// CHECK-NEXT: ret i16 [[TMP2]]
@@ -2846,7 +2846,7 @@ mve_pred16_t test_vcmpltq_n_f16(float16x8_t a, float16_t b)
// CHECK-NEXT: entry:
// CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement <4 x float> poison, float [[B:%.*]], i64 0
// CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector <4 x float> [[DOTSPLATINSERT]], <4 x float> poison, <4 x i32> zeroinitializer
-// CHECK-NEXT: [[TMP0:%.*]] = fcmp olt <4 x float> [[A:%.*]], [[DOTSPLAT]]
+// CHECK-NEXT: [[TMP0:%.*]] = fcmp ult <4 x float> [[A:%.*]], [[DOTSPLAT]]
// CHECK-NEXT: [[TMP1:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v4i1(<4 x i1> [[TMP0]])
// CHECK-NEXT: [[TMP2:%.*]] = trunc i32 [[TMP1]] to i16
// CHECK-NEXT: ret i16 [[TMP2]]
@@ -2918,7 +2918,7 @@ mve_pred16_t test_vcmpltq_n_s32(int32x4_t a, int32_t b)
// CHECK-NEXT: entry:
// CHECK-NEXT: [[TMP0:%.*]] = zext i16 [[P:%.*]] to i32
// CHECK-NEXT: [[TMP1:%.*]] = call <8 x i1> @llvm.arm.mve.pred.i2v.v8i1(i32 [[TMP0]])
-// CHECK-NEXT: [[TMP2:%.*]] = fcmp olt <8 x half> [[A:%.*]], [[B:%.*]]
+// CHECK-NEXT: [[TMP2:%.*]] = fcmp ult <8 x half> [[A:%.*]], [[B:%.*]]
// CHECK-NEXT: [[TMP3:%.*]] = and <8 x i1> [[TMP1]], [[TMP2]]
// CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v8i1(<8 x i1> [[TMP3]])
// CHECK-NEXT: [[TMP5:%.*]] = trunc i32 [[TMP4]] to i16
@@ -2937,7 +2937,7 @@ mve_pred16_t test_vcmpltq_m_f16(float16x8_t a, float16x8_t b, mve_pred16_t p)
// CHECK-NEXT: entry:
// CHECK-NEXT: [[TMP0:%.*]] = zext i16 [[P:%.*]] to i32
// CHECK-NEXT: [[TMP1:%.*]] = call <4 x i1> @llvm.arm.mve.pred.i2v.v4i1(i32 [[TMP0]])
-// CHECK-NEXT: [[TMP2:%.*]] = fcmp olt <4 x float> [[A:%.*]], [[B:%.*]]
+// CHECK-NEXT: [[TMP2:%.*]] = fcmp ult <4 x float> [[A:%.*]], [[B:%.*]]
// CHECK-NEXT: [[TMP3:%.*]] = and <4 x i1> [[TMP1]], [[TMP2]]
// CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v4i1(<4 x i1> [[TMP3]])
// CHECK-NEXT: [[TMP5:%.*]] = trunc i32 [[TMP4]] to i16
@@ -3015,7 +3015,7 @@ mve_pred16_t test_vcmpltq_m_s32(int32x4_t a, int32x4_t b, mve_pred16_t p)
// CHECK-NEXT: [[TMP1:%.*]] = call <8 x i1> @llvm.arm.mve.pred.i2v.v8i1(i32 [[TMP0]])
// CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement <8 x half> poison, half [[B:%.*]], i64 0
// CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector <8 x half> [[DOTSPLATINSERT]], <8 x half> poison, <8 x i32> zeroinitializer
-// CHECK-NEXT: [[TMP2:%.*]] = fcmp olt <8 x half> [[A:%.*]], [[DOTSPLAT]]
+// CHECK-NEXT: [[TMP2:%.*]] = fcmp ult <8 x half> [[A:%.*]], [[DOTSPLAT]]
// CHECK-NEXT: [[TMP3:%.*]] = and <8 x i1> [[TMP1]], [[TMP2]]
// CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v8i1(<8 x i1> [[TMP3]])
// CHECK-NEXT: [[TMP5:%.*]] = trunc i32 [[TMP4]] to i16
@@ -3036,7 +3036,7 @@ mve_pred16_t test_vcmpltq_m_n_f16(float16x8_t a, float16_t b, mve_pred16_t p)
// CHECK-NEXT: [[TMP1:%.*]] = call <4 x i1> @llvm.arm.mve.pred.i2v.v4i1(i32 [[TMP0]])
// CHECK-NEXT: [[DOTSPLATINSERT:%.*]] = insertelement <4 x float> poison, float [[B:%.*]], i64 0
// CHECK-NEXT: [[DOTSPLAT:%.*]] = shufflevector <4 x float> [[DOTSPLATINSERT]], <4 x float> poison, <4 x i32> zeroinitializer
-// CHECK-NEXT: [[TMP2:%.*]] = fcmp olt <4 x float> [[A:%.*]], [[DOTSPLAT]]
+// CHECK-NEXT: [[TMP2:%.*]] = fcmp ult <4 x float> [[A:%.*]], [[DOTSPLAT]]
// CHECK-NEXT: [[TMP3:%.*]] = and <4 x i1> [[TMP1]], [[TMP2]]
// CHECK-NEXT: [[TMP4:%.*]] = call i32 @llvm.arm.mve.pred.v2i.v4i1(<4 x i1> [[TMP3]])
// CHECK-NEXT: [[TMP5:%.*]] = trunc i32 [[TMP4]] to i16
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