[llvm] 5537230 - [InstSimplify] Fix a scalable-vector crash
Fraser Cormack via llvm-commits
llvm-commits at lists.llvm.org
Wed Jun 28 09:11:05 PDT 2023
Author: Fraser Cormack
Date: 2023-06-28T17:07:10+01:00
New Revision: 55372309a4c757af17f7dc33e5b686cf8565997f
URL: https://github.com/llvm/llvm-project/commit/55372309a4c757af17f7dc33e5b686cf8565997f
DIFF: https://github.com/llvm/llvm-project/commit/55372309a4c757af17f7dc33e5b686cf8565997f.diff
LOG: [InstSimplify] Fix a scalable-vector crash
D143505 fixed/simplified folding of operations with SNaN operands. In
doing so it introduced a crash when handling scalable vector types,
wherein the scalable-vector ConstantVector was cast to a ConstantFP.
Since we know by that point in the code that if we've found a NaN, we're
dealing with a scalable-vector splat (as there are no other kinds of
scalable-vector constant for which that holds), we can grab the splatted
value and re-use the existing code, which will automatically splat the
new NaN back to a scalable vector for us.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D153566
Added:
Modified:
llvm/lib/Analysis/InstructionSimplify.cpp
llvm/test/Transforms/InstSimplify/fp-nan.ll
Removed:
################################################################################
diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
index 27fbff3743a19..54ce6264ef7ab 100644
--- a/llvm/lib/Analysis/InstructionSimplify.cpp
+++ b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -5466,6 +5466,15 @@ static Constant *propagateNaN(Constant *In) {
if (!In->isNaN())
return ConstantFP::getNaN(Ty);
+ // If we known this is a NaN, and it's scalable vector, we must have a splat
+ // on our hands. Grab that before splatting a QNaN constant.
+ if (isa<ScalableVectorType>(Ty)) {
+ auto *Splat = In->getSplatValue();
+ assert(Splat && Splat->isNaN() &&
+ "Found a scalable-vector NaN but not a splat");
+ In = Splat;
+ }
+
// Propagate an existing QNaN constant. If it is an SNaN, make it quiet, but
// preserve the sign/payload.
return ConstantFP::get(Ty, cast<ConstantFP>(In)->getValue().makeQuiet());
diff --git a/llvm/test/Transforms/InstSimplify/fp-nan.ll b/llvm/test/Transforms/InstSimplify/fp-nan.ll
index 620bda1461772..fad7a0593e372 100644
--- a/llvm/test/Transforms/InstSimplify/fp-nan.ll
+++ b/llvm/test/Transforms/InstSimplify/fp-nan.ll
@@ -49,6 +49,22 @@ define <2 x float> @fsub_nan_op1_vec(<2 x float> %x) {
ret <2 x float> %r
}
+define <vscale x 1 x float> @fsub_nan_op1_scalable_vec_0(<vscale x 1 x float> %x) {
+; CHECK-LABEL: @fsub_nan_op1_scalable_vec_0(
+; CHECK-NEXT: ret <vscale x 1 x float> shufflevector (<vscale x 1 x float> insertelement (<vscale x 1 x float> poison, float 0x7FF9000000000000, i64 0), <vscale x 1 x float> poison, <vscale x 1 x i32> zeroinitializer)
+;
+ %r = fsub <vscale x 1 x float> %x, shufflevector (<vscale x 1 x float> insertelement (<vscale x 1 x float> poison, float 0x7FF1000000000000, i64 0), <vscale x 1 x float> poison, <vscale x 1 x i32> zeroinitializer)
+ ret <vscale x 1 x float> %r
+}
+
+define <vscale x 1 x float> @fsub_nan_op1_scalable_vec_1(<vscale x 1 x float> %x) {
+; CHECK-LABEL: @fsub_nan_op1_scalable_vec_1(
+; CHECK-NEXT: ret <vscale x 1 x float> shufflevector (<vscale x 1 x float> insertelement (<vscale x 1 x float> poison, float 0xFFF9000000000000, i64 0), <vscale x 1 x float> poison, <vscale x 1 x i32> zeroinitializer)
+;
+ %r = fsub <vscale x 1 x float> %x, shufflevector (<vscale x 1 x float> insertelement (<vscale x 1 x float> poison, float 0xFFF1000000000000, i64 0), <vscale x 1 x float> poison, <vscale x 1 x i32> zeroinitializer)
+ ret <vscale x 1 x float> %r
+}
+
; Signaling and signed - make quiet and preserve the payload and signbit
define double @fmul_nan_op0(double %x) {
@@ -67,6 +83,22 @@ define <2 x double> @fmul_nan_op0_vec(<2 x double> %x) {
ret <2 x double> %r
}
+define <vscale x 1 x double> @fmul_nan_op0_scalable_vec_0(<vscale x 1 x double> %x) {
+; CHECK-LABEL: @fmul_nan_op0_scalable_vec_0(
+; CHECK-NEXT: ret <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF8000000000001, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+;
+ %r = fmul <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF0000000000001, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer), %x
+ ret <vscale x 1 x double> %r
+}
+
+define <vscale x 1 x double> @fmul_nan_op0_scalable_vec_1(<vscale x 1 x double> %x) {
+; CHECK-LABEL: @fmul_nan_op0_scalable_vec_1(
+; CHECK-NEXT: ret <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF8DEADDEADDEAD, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+;
+ %r = fmul <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF0DEADDEADDEAD, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer), %x
+ ret <vscale x 1 x double> %r
+}
+
; Vector type
define <2 x float> @fmul_nan_op1(<2 x float> %x) {
@@ -77,6 +109,14 @@ define <2 x float> @fmul_nan_op1(<2 x float> %x) {
ret <2 x float> %r
}
+define <vscale x 1 x double> @fmul_nan_op1_scalable_vec(<vscale x 1 x double> %x) {
+; CHECK-LABEL: @fmul_nan_op1_scalable_vec(
+; CHECK-NEXT: ret <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0x7FF8000000000000, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+;
+ %r = fmul <vscale x 1 x double> %x, shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0x7FF8000000000000, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+ ret <vscale x 1 x double> %r
+}
+
; Vector signed and non-zero payload
define <2 x double> @fdiv_nan_op0(<2 x double> %x) {
@@ -87,6 +127,14 @@ define <2 x double> @fdiv_nan_op0(<2 x double> %x) {
ret <2 x double> %r
}
+define <vscale x 1 x double> @fdivl_nan_op0_scalable_vec(<vscale x 1 x double> %x) {
+; CHECK-LABEL: @fdivl_nan_op0_scalable_vec(
+; CHECK-NEXT: ret <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF800000000000F, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+;
+ %r = fdiv <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF800000000000F, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer), %x
+ ret <vscale x 1 x double> %r
+}
+
; Vector with
diff erent NaN constant elements
define <2 x half> @fdiv_nan_op1(<2 x half> %x) {
@@ -97,6 +145,14 @@ define <2 x half> @fdiv_nan_op1(<2 x half> %x) {
ret <2 x half> %r
}
+define <vscale x 1 x half> @fdiv_nan_op1_scalable_vec(<vscale x 1 x half> %x) {
+; CHECK-LABEL: @fdiv_nan_op1_scalable_vec(
+; CHECK-NEXT: ret <vscale x 1 x half> shufflevector (<vscale x 1 x half> insertelement (<vscale x 1 x half> poison, half 0xH7FFF, i64 0), <vscale x 1 x half> poison, <vscale x 1 x i32> zeroinitializer)
+;
+ %r = fdiv <vscale x 1 x half> %x, shufflevector (<vscale x 1 x half> insertelement (<vscale x 1 x half> poison, half 0xH7FFF, i64 0), <vscale x 1 x half> poison, <vscale x 1 x i32> zeroinitializer)
+ ret <vscale x 1 x half> %r
+}
+
; Vector with poison element
define <2 x double> @fsub_nan_poison_op1(<2 x double> %x) {
@@ -161,6 +217,14 @@ define <2 x double> @fneg_nan_2(<2 x double> %x) {
ret <2 x double> %r
}
+define <vscale x 1 x double> @fneg_nan_2_scalable_vec() {
+; CHECK-LABEL: @fneg_nan_2_scalable_vec(
+; CHECK-NEXT: ret <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF9234567890ABC, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+;
+ %r = fsub <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double -0.0, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer), shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF1234567890ABC, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+ ret <vscale x 1 x double> %r
+}
+
define <2 x double> @unary_fneg_nan_2(<2 x double> %x) {
; CHECK-LABEL: @unary_fneg_nan_2(
; CHECK-NEXT: ret <2 x double> <double 0x7FF1234567890ABC, double 0xFFF0000000000001>
@@ -169,6 +233,26 @@ define <2 x double> @unary_fneg_nan_2(<2 x double> %x) {
ret <2 x double> %r
}
+; FIXME: This doesn't behave the same way as the fixed-length vectors above
+define <vscale x 1 x double> @unary_fneg_nan_2_scalable_vec_0() {
+; CHECK-LABEL: @unary_fneg_nan_2_scalable_vec_0(
+; CHECK-NEXT: [[R:%.*]] = fneg <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF1234567890ABC, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+; CHECK-NEXT: ret <vscale x 1 x double> [[R]]
+;
+ %r = fneg <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0xFFF1234567890ABC, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+ ret <vscale x 1 x double> %r
+}
+
+; FIXME: This doesn't behave the same way as the fixed-length vectors above
+define <vscale x 1 x double> @unary_fneg_nan_2_scalable_vec_1() {
+; CHECK-LABEL: @unary_fneg_nan_2_scalable_vec_1(
+; CHECK-NEXT: [[R:%.*]] = fneg <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0x7FF0000000000001, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+; CHECK-NEXT: ret <vscale x 1 x double> [[R]]
+;
+ %r = fneg <vscale x 1 x double> shufflevector (<vscale x 1 x double> insertelement (<vscale x 1 x double> poison, double 0x7FF0000000000001, i64 0), <vscale x 1 x double> poison, <vscale x 1 x i32> zeroinitializer)
+ ret <vscale x 1 x double> %r
+}
+
; Repeat all tests with fast-math-flags. Alternate 'nnan' and 'fast' for more coverage.
define float @fadd_nan_op0_nnan(float %x) {
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