https://github.com/danbrown-amd updated https://github.com/llvm/llvm-project/pull/221105
>From fd03dab0bfc9b9c3acbe02f83850bfa70284c08a Mon Sep 17 00:00:00 2001 From: danbrown-amd <[email protected]> Date: Thu, 3 Sep 2026 18:46:23 -0600 Subject: [PATCH 1/3] Use icmp-ne instead of truncation on boolean load Fixes #140824 Assisted-by: Claude Sonnet 4 --- clang/lib/CodeGen/CGExpr.cpp | 5 +++-- clang/lib/Frontend/CompilerInvocation.cpp | 6 ++++++ clang/test/CodeGenHLSL/strict-bool.hlsl | 2 +- 3 files changed, 10 insertions(+), 3 deletions(-) diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp index 019159dd620fd..f5d053e6b6713 100644 --- a/clang/lib/CodeGen/CGExpr.cpp +++ b/clang/lib/CodeGen/CGExpr.cpp @@ -5681,9 +5681,10 @@ EmitExtVectorElementExpr(const ExtVectorElementExpr *E) { Address VecMem = CreateMemTemp(E->getBase()->getType()); // need to zero extend an hlsl boolean vector to store it back to memory QualType Ty = E->getBase()->getType(); - llvm::Type *LTy = convertTypeForLoadStore(Ty, Vec->getType()); - if (LTy->getScalarSizeInBits() > Vec->getType()->getScalarSizeInBits()) + if (getLangOpts().HLSL && Ty->isExtVectorBoolType()) { + llvm::Type *LTy = convertTypeForLoadStore(Ty, Vec->getType()); Vec = Builder.CreateZExt(Vec, LTy); + } Builder.CreateStore(Vec, VecMem); Base = MakeAddrLValue(VecMem, Ty, AlignmentSource::Decl); } diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp index c9281c2a6d6b4..0a3a235fbac33 100644 --- a/clang/lib/Frontend/CompilerInvocation.cpp +++ b/clang/lib/Frontend/CompilerInvocation.cpp @@ -657,6 +657,12 @@ static bool FixupInvocation(CompilerInvocation &Invocation, Warnings.insert(Warnings.begin(), "vector-conversion"); if (!llvm::is_contained(Warnings, "matrix-conversion")) Warnings.insert(Warnings.begin(), "matrix-conversion"); + + // HLSL booleans in memory are i32; any non-zero value is true. + // Use icmp-ne rather than truncation to avoid InstCombine rewriting + // trunc i32 to i1 into an illegal wide <N x i1> bitcast (issue #140824). + if (!Args.hasArg(OPT_load_bool_from_mem)) + CodeGenOpts.setLoadBoolFromMem(CodeGenOptions::BoolFromMem::NonZero); } // When these options are used, the compiler is allowed to apply diff --git a/clang/test/CodeGenHLSL/strict-bool.hlsl b/clang/test/CodeGenHLSL/strict-bool.hlsl index 31867065e77a3..30bdc02231fa5 100644 --- a/clang/test/CodeGenHLSL/strict-bool.hlsl +++ b/clang/test/CodeGenHLSL/strict-bool.hlsl @@ -1,6 +1,6 @@ // RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -O1 -load-bool-from-mem=truncate -emit-llvm -o - %s | FileCheck %s -check-prefixes=CHECK-TRUNCATE // RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -O1 -load-bool-from-mem=nonzero -emit-llvm -o - %s | FileCheck %s -check-prefixes=CHECK-NONZERO -// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -O0 -emit-llvm -o - %s | FileCheck %s -check-prefixes=CHECK-NONZERO +// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -O1 -emit-llvm -o - %s | FileCheck %s -check-prefixes=CHECK-NONZERO typedef bool bool8_t __attribute__((ext_vector_type(8))); extern bool8_t vec; >From a54e001a8ec8dc38aaaed2eed75b54af43a15fa8 Mon Sep 17 00:00:00 2001 From: danbrown-amd <[email protected]> Date: Thu, 8 Oct 2026 16:30:54 -0600 Subject: [PATCH 2/3] Revert test and one source file as per review comments --- clang/lib/CodeGen/CGExpr.cpp | 5 ++--- clang/test/CodeGenHLSL/strict-bool.hlsl | 2 +- 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp index f5d053e6b6713..019159dd620fd 100644 --- a/clang/lib/CodeGen/CGExpr.cpp +++ b/clang/lib/CodeGen/CGExpr.cpp @@ -5681,10 +5681,9 @@ EmitExtVectorElementExpr(const ExtVectorElementExpr *E) { Address VecMem = CreateMemTemp(E->getBase()->getType()); // need to zero extend an hlsl boolean vector to store it back to memory QualType Ty = E->getBase()->getType(); - if (getLangOpts().HLSL && Ty->isExtVectorBoolType()) { - llvm::Type *LTy = convertTypeForLoadStore(Ty, Vec->getType()); + llvm::Type *LTy = convertTypeForLoadStore(Ty, Vec->getType()); + if (LTy->getScalarSizeInBits() > Vec->getType()->getScalarSizeInBits()) Vec = Builder.CreateZExt(Vec, LTy); - } Builder.CreateStore(Vec, VecMem); Base = MakeAddrLValue(VecMem, Ty, AlignmentSource::Decl); } diff --git a/clang/test/CodeGenHLSL/strict-bool.hlsl b/clang/test/CodeGenHLSL/strict-bool.hlsl index 30bdc02231fa5..31867065e77a3 100644 --- a/clang/test/CodeGenHLSL/strict-bool.hlsl +++ b/clang/test/CodeGenHLSL/strict-bool.hlsl @@ -1,6 +1,6 @@ // RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -O1 -load-bool-from-mem=truncate -emit-llvm -o - %s | FileCheck %s -check-prefixes=CHECK-TRUNCATE // RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -O1 -load-bool-from-mem=nonzero -emit-llvm -o - %s | FileCheck %s -check-prefixes=CHECK-NONZERO -// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -O1 -emit-llvm -o - %s | FileCheck %s -check-prefixes=CHECK-NONZERO +// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.3-library -O0 -emit-llvm -o - %s | FileCheck %s -check-prefixes=CHECK-NONZERO typedef bool bool8_t __attribute__((ext_vector_type(8))); extern bool8_t vec; >From 3591f213ca47a3e79e4f86de7a5d8e561250d358 Mon Sep 17 00:00:00 2001 From: danbrown-amd <[email protected]> Date: Tue, 13 Oct 2026 23:10:48 -0600 Subject: [PATCH 3/3] Address additional review comments --- clang/include/clang/Basic/DiagnosticFrontendKinds.td | 3 +++ clang/lib/Driver/ToolChains/HLSL.cpp | 1 + clang/lib/Frontend/CompilerInvocation.cpp | 4 ++++ clang/test/Driver/HLSL/load-bool-from-mem.hlsl | 3 +++ 4 files changed, 11 insertions(+) create mode 100644 clang/test/Driver/HLSL/load-bool-from-mem.hlsl diff --git a/clang/include/clang/Basic/DiagnosticFrontendKinds.td b/clang/include/clang/Basic/DiagnosticFrontendKinds.td index 66eeb08034bf4..2281836406e63 100644 --- a/clang/include/clang/Basic/DiagnosticFrontendKinds.td +++ b/clang/include/clang/Basic/DiagnosticFrontendKinds.td @@ -514,6 +514,9 @@ def warn_hlsl_signature_packing_ignored : Warning< def warn_hlsl_failed_to_embed_source : Warning<"failed to embed source for '%0' into dx.source.contents">, InGroup<HLSLDXCCompat>; +def warn_hlsl_bool_from_mem + : Warning<"-load-bool-from-mem=%0 ignored for HLSL (always nonzero)">, + InGroup<OptionIgnored>, DefaultWarn; def err_data_layout_mismatch : Error<"backend data layout '%0' does not match " "expected target description '%1'">; diff --git a/clang/lib/Driver/ToolChains/HLSL.cpp b/clang/lib/Driver/ToolChains/HLSL.cpp index b5356f1ec45d3..7b0be0ab1f402 100644 --- a/clang/lib/Driver/ToolChains/HLSL.cpp +++ b/clang/lib/Driver/ToolChains/HLSL.cpp @@ -689,4 +689,5 @@ void HLSLToolChain::addClangWarningOptions(ArgStringList &CC1Args) const { CC1Args.push_back("-Wconversion"); CC1Args.push_back("-Wvector-conversion"); CC1Args.push_back("-Wmatrix-conversion"); + CC1Args.push_back("-load-bool-from-mem=nonzero"); } diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp index 0a3a235fbac33..49246f7b6d4d0 100644 --- a/clang/lib/Frontend/CompilerInvocation.cpp +++ b/clang/lib/Frontend/CompilerInvocation.cpp @@ -663,6 +663,10 @@ static bool FixupInvocation(CompilerInvocation &Invocation, // trunc i32 to i1 into an illegal wide <N x i1> bitcast (issue #140824). if (!Args.hasArg(OPT_load_bool_from_mem)) CodeGenOpts.setLoadBoolFromMem(CodeGenOptions::BoolFromMem::NonZero); + else if (CodeGenOpts.getLoadBoolFromMem() != + CodeGenOptions::BoolFromMem::NonZero) + Diags.Report(diag::warn_hlsl_bool_from_mem) + << Args.getLastArg(OPT_load_bool_from_mem)->getValue(); } // When these options are used, the compiler is allowed to apply diff --git a/clang/test/Driver/HLSL/load-bool-from-mem.hlsl b/clang/test/Driver/HLSL/load-bool-from-mem.hlsl new file mode 100644 index 0000000000000..23ee8cca8b6de --- /dev/null +++ b/clang/test/Driver/HLSL/load-bool-from-mem.hlsl @@ -0,0 +1,3 @@ +// RUN: %clang_dxc -T cs_6_3 -### %s 2>&1 | FileCheck %s + +// CHECK: "-load-bool-from-mem=nonzero" _______________________________________________ cfe-commits mailing list [email protected] https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
