[clang] [Clang] Fix crash for incompatible types in inline assembly (PR #119098)

[via cfe-commits]

https://github.com/AdUhTkJm updated https://github.com/llvm/llvm-project/pull/119098

>From 9780af34b63423344783ece5e8ec89de5b815c7f Mon Sep 17 00:00:00 2001
From: AdUhTkJm <2292398666 at qq.com>
Date: Sun, 8 Dec 2024 08:07:59 +0800
Subject: [PATCH] [Clang] Fix crash for incompatible types in inline assembly

---
 clang/lib/Sema/SemaStmtAsm.cpp | 13 ++++++++++++-
 clang/test/Sema/asm.c          |  6 ++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/clang/lib/Sema/SemaStmtAsm.cpp b/clang/lib/Sema/SemaStmtAsm.cpp
index 0b272b806391c4..770b59d0c3ebfa 100644
--- a/clang/lib/Sema/SemaStmtAsm.cpp
+++ b/clang/lib/Sema/SemaStmtAsm.cpp
@@ -664,11 +664,22 @@ StmtResult Sema::ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple,
       SmallerValueMentioned |= OutSize < InSize;
     }
 
+    // If the input is an integer register while the output is floating point,
+    // there is no way they can work together.
+    bool FPBoundToInt = false;
+    if (InputDomain != AD_FP && OutputDomain == AD_FP) {
+      FPBoundToInt = true;
+    }
+    if (InputDomain == AD_FP && OutputDomain != AD_FP) {
+      FPBoundToInt = true;
+    }
+
     // If the smaller value wasn't mentioned in the asm string, and if the
     // output was a register, just extend the shorter one to the size of the
     // larger one.
-    if (!SmallerValueMentioned && InputDomain != AD_Other &&
+    if (!SmallerValueMentioned && !FPBoundToInt && InputDomain != AD_Other &&
         OutputConstraintInfos[TiedTo].allowsRegister()) {
+
       // FIXME: GCC supports the OutSize to be 128 at maximum. Currently codegen
       // crash when the size larger than the register size. So we limit it here.
       if (OutTy->isStructureType() &&
diff --git a/clang/test/Sema/asm.c b/clang/test/Sema/asm.c
index a9cff5947ef5d0..f925849b82b33b 100644
--- a/clang/test/Sema/asm.c
+++ b/clang/test/Sema/asm.c
@@ -365,3 +365,9 @@ void test19(long long x)
   // FIXME: This case should be supported by codegen, but it fails now.
   asm ("" : "=rm" (x): "0" (e)); // expected-error {{unsupported inline asm: input with type 'st_size128' (aka 'struct _st_size128') matching output with type 'long long'}}
 }
+
+// PR119098
+void test20(char x) {
+  double value;
+  asm ("fabs" : "=t" (value): "0" (x)); // expected-error {{unsupported inline asm: input with type 'char' matching output with type 'double'}}
+}
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