[llvm] 1d3d2f4 - [SPIR-V] Lower G_SSHLSAT and G_USHLSAT (#206490)

[via llvm-commits]

Author: Arseniy Obolenskiy
Date: 2026-06-30T11:09:16+02:00
New Revision: 1d3d2f43dd00a569bb77e436a5e318baf7de7dbd

URL: https://github.com/llvm/llvm-project/commit/1d3d2f43dd00a569bb77e436a5e318baf7de7dbd
DIFF: https://github.com/llvm/llvm-project/commit/1d3d2f43dd00a569bb77e436a5e318baf7de7dbd.diff

LOG: [SPIR-V] Lower G_SSHLSAT and G_USHLSAT (#206490)

Added: 
    llvm/test/CodeGen/SPIRV/sat-shifts.ll

Modified: 
    llvm/lib/Target/SPIRV/SPIRVLegalizerInfo.cpp

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/SPIRV/SPIRVLegalizerInfo.cpp b/llvm/lib/Target/SPIRV/SPIRVLegalizerInfo.cpp
index 21fa782c4cc9e..1da5cc9400b0c 100644
--- a/llvm/lib/Target/SPIRV/SPIRVLegalizerInfo.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVLegalizerInfo.cpp
@@ -329,6 +329,8 @@ SPIRVLegalizerInfo::SPIRVLegalizerInfo(const SPIRVSubtarget &ST) {
       .legalFor(allIntScalarsAndVectors)
       .legalIf(extendedScalarsAndVectors);
 
+  getActionDefinitionsBuilder({G_SSHLSAT, G_USHLSAT}).lower();
+
   getActionDefinitionsBuilder(G_STRICT_FLDEXP)
       .legalForCartesianProduct(allFloatScalarsAndVectors, allIntScalars);
 

diff  --git a/llvm/test/CodeGen/SPIRV/sat-shifts.ll b/llvm/test/CodeGen/SPIRV/sat-shifts.ll
new file mode 100644
index 0000000000000..d5cd705543eff
--- /dev/null
+++ b/llvm/test/CodeGen/SPIRV/sat-shifts.ll
@@ -0,0 +1,57 @@
+; RUN: llc -verify-machineinstrs -O0 -mtriple=spirv64-unknown-unknown %s -o - | FileCheck %s
+; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv64-unknown-unknown %s -o - -filetype=obj | spirv-val %}
+
+; CHECK-DAG: OpName %[[#Foo:]] "foo"
+; CHECK-DAG: OpName %[[#Bar:]] "bar"
+
+; CHECK: %[[#Foo]] = OpFunction
+; CHECK: %[[#]] = OpShiftLeftLogical %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpShiftRightArithmetic %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpSLessThan %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpSelect %[[#]] %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpINotEqual %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpSelect %[[#]] %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpShiftLeftLogical %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpShiftRightLogical %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpINotEqual %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpSelect %[[#]] %[[#]] %[[#]] %[[#]]
+
+; CHECK: %[[#Bar]] = OpFunction
+; CHECK: %[[#]] = OpShiftLeftLogical %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpShiftRightArithmetic %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpSLessThan %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpSelect %[[#]] %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpINotEqual %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpSelect %[[#]] %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpShiftLeftLogical %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpShiftRightLogical %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpINotEqual %[[#]] %[[#]] %[[#]]
+; CHECK: %[[#]] = OpSelect %[[#]] %[[#]] %[[#]] %[[#]]
+
+define spir_func void @foo(i16 %x, i16 %y) {
+entry:
+  %r1 = tail call i16 @llvm.sshl.sat.i16(i16 %x, i16 %y)
+  store i16 %r1, ptr @G_r1_foo
+  %r2 = tail call i16 @llvm.ushl.sat.i16(i16 %x, i16 %y)
+  store i16 %r2, ptr @G_r2_foo
+  ret void
+}
+
+define spir_func void @bar(<4 x i32> %x, <4 x i32> %y) {
+entry:
+  %r1 = tail call <4 x i32> @llvm.sshl.sat.v4i32(<4 x i32> %x, <4 x i32> %y)
+  store <4 x i32> %r1, ptr @G_r1_bar
+  %r2 = tail call <4 x i32> @llvm.ushl.sat.v4i32(<4 x i32> %x, <4 x i32> %y)
+  store <4 x i32> %r2, ptr @G_r2_bar
+  ret void
+}
+
+ at G_r1_foo = global i16 0
+ at G_r2_foo = global i16 0
+ at G_r1_bar = global <4 x i32> zeroinitializer
+ at G_r2_bar = global <4 x i32> zeroinitializer
+
+declare i16 @llvm.sshl.sat.i16(i16, i16)
+declare i16 @llvm.ushl.sat.i16(i16, i16)
+declare <4 x i32> @llvm.sshl.sat.v4i32(<4 x i32>, <4 x i32>)
+declare <4 x i32> @llvm.ushl.sat.v4i32(<4 x i32>, <4 x i32>)