[llvm] 0e1b093 - [SPIR-V] Preserve signed i1 semantics in sitofp (#209232)

[via llvm-commits]

Author: Arseniy Obolenskiy
Date: 2026-07-17T11:29:23+02:00
New Revision: 0e1b0935ff6f326ba1b9c2d23ba9fa7b41e6941d

URL: https://github.com/llvm/llvm-project/commit/0e1b0935ff6f326ba1b9c2d23ba9fa7b41e6941d
DIFF: https://github.com/llvm/llvm-project/commit/0e1b0935ff6f326ba1b9c2d23ba9fa7b41e6941d.diff

LOG: [SPIR-V] Preserve signed i1 semantics in sitofp (#209232)

selectIToF hardcoded IsSigned=false when materializing the bool-to-int
conversion, so sitofp i1 true was miscompiled as 1.0 instead of -1.0

Added: 
    

Modified: 
    llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp
    llvm/test/CodeGen/SPIRV/sitofp-with-bool.ll
    llvm/test/CodeGen/SPIRV/uitofp-with-bool.ll

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp b/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp
index 15bb399c2ca09..deaf6add76ed9 100644
--- a/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp
@@ -4662,7 +4662,7 @@ bool SPIRVInstructionSelector::selectIToF(Register ResVReg,
       TmpType = GR.getOrCreateSPIRVVectorType(TmpType, NumElts, I, TII);
     }
     SrcReg = createVirtualRegister(TmpType, &GR, MRI, MRI->getMF());
-    selectBoolToInt(SrcReg, TmpType, I.getOperand(1).getReg(), I, false);
+    selectBoolToInt(SrcReg, TmpType, I.getOperand(1).getReg(), I, IsSigned);
   }
   return selectOpWithSrcs(ResVReg, ResType, I, {SrcReg}, Opcode);
 }

diff  --git a/llvm/test/CodeGen/SPIRV/sitofp-with-bool.ll b/llvm/test/CodeGen/SPIRV/sitofp-with-bool.ll
index 22a6c73cc753f..4d39e1adaaea5 100644
--- a/llvm/test/CodeGen/SPIRV/sitofp-with-bool.ll
+++ b/llvm/test/CodeGen/SPIRV/sitofp-with-bool.ll
@@ -5,14 +5,14 @@
 ; CHECK-DAG: %[[#float:]] = OpTypeFloat 32
 ; CHECK-DAG: %[[#bool:]] = OpTypeBool
 ; CHECK-DAG: %[[#zero:]] = OpConstantNull %[[#int_32]]
-; CHECK-DAG: %[[#one:]] = OpConstant %[[#int_32]] 1
+; CHECK-DAG: %[[#mone:]] = OpConstant %[[#int_32]] 4294967295
 ; CHECK-DAG: %[[#ptr:]] = OpTypePointer CrossWorkgroup %[[#float]]
 
 ; CHECK: OpFunction
 ; CHECK: %[[#A:]] = OpFunctionParameter %[[#ptr]]
 ; CHECK: %[[#B:]] = OpFunctionParameter %[[#]]
 ; CHECK: %[[#cmp_res:]] = OpSGreaterThan %[[#bool]] %[[#B]] %[[#zero]]
-; CHECK: %[[#select_res:]] = OpSelect %[[#int_32]] %[[#cmp_res]] %[[#one]] %[[#zero]]
+; CHECK: %[[#select_res:]] = OpSelect %[[#int_32]] %[[#cmp_res]] %[[#mone]] %[[#zero]]
 ; CHECK: %[[#stof_res:]] = OpConvertSToF %[[#]] %[[#select_res]]
 ; CHECK: OpStore %[[#A]] %[[#stof_res]]
 

diff  --git a/llvm/test/CodeGen/SPIRV/uitofp-with-bool.ll b/llvm/test/CodeGen/SPIRV/uitofp-with-bool.ll
index 7a702e54aadf8..e744becf3518f 100644
--- a/llvm/test/CodeGen/SPIRV/uitofp-with-bool.ll
+++ b/llvm/test/CodeGen/SPIRV/uitofp-with-bool.ll
@@ -143,11 +143,11 @@ entry:
 ; SPV: %[[#ufp2:]] = OpConvertUToF %[[#vec_float]] %[[#ufp2_res]]
   %ufp2 = uitofp <2 x i1> %i1v to <2 x float>
   store <2 x float> %ufp2, ptr @G_ufp2
-; SPV: %[[#sfp1_res:]] = OpSelect %[[#int_32]] %[[#i1s]] %[[#one_32]] %[[#zero_32]]
+; SPV: %[[#sfp1_res:]] = OpSelect %[[#int_32]] %[[#i1s]] %[[#mone_32]] %[[#zero_32]]
 ; SPV: %[[#sfp1:]] = OpConvertSToF %[[#float]] %[[#sfp1_res]]
   %sfp1 = sitofp i1 %i1s to float
   store float %sfp1, ptr @G_sfp1
-; SPV: %[[#sfp2_res:]] = OpSelect %[[#vec_32]] %[[#i1v]] %[[#ones_32]] %[[#zeros_32]]
+; SPV: %[[#sfp2_res:]] = OpSelect %[[#vec_32]] %[[#i1v]] %[[#mones_32]] %[[#zeros_32]]
 ; SPV: %[[#sfp2:]] = OpConvertSToF %[[#vec_float]] %[[#sfp2_res]]
   %sfp2 = sitofp <2 x i1> %i1v to <2 x float>
   store <2 x float> %sfp2, ptr @G_sfp2