[llvm] Pre-commit test to verify mode change in fp constrained operations (PR #88858)

[Abhinav Garg via llvm-commits]

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@@ -0,0 +1,28 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -verify-machineinstrs %s -o - | FileCheck -check-prefix=GCN %s
+
+; The si-mode-register pass is changing the default mode for FP constrained  operations.
+; It must ignore for strictfp functions.
+
+define hidden fastcc double @ignoreStrictfp(double noundef %0, double noundef %1) unnamed_addr #0 {
+; GCN-LABEL: ignoreStrictfp:
+; GCN:       ; %bb.0:
+; GCN-NEXT:    s_waitcnt vmcnt(0) expcnt(0) lgkmcnt(0)
+; GCN-NEXT:    s_setreg_imm32_b32 hwreg(HW_REG_MODE, 2, 2), 1
+; GCN-NEXT:    s_nop 1
+; GCN-NEXT:     s_setreg_imm32_b32 hwreg(HW_REG_MODE, 2, 1), 0
+; GCN-NEXT:    v_add_f64 v[0:1], v[0:1], v[2:3]
+; GCN-NEXT:    s_nop 0
+; GCN-NEXT:    s_setreg_imm32_b32 hwreg(HW_REG_MODE, 2, 2), 0
+; GCN-NEXT:    s_setpc_b64 s[30:31]
+  tail call void @llvm.amdgcn.s.setreg(i32 2177, i32 1)
+  %3 = tail call double @llvm.experimental.constrained.fadd.f64(double %0, double %1, metadata !"round.dynamic", metadata !"fpexcept.strict") #0
+  tail call void @llvm.amdgcn.s.setreg(i32 2177, i32 0)
+  ret double %3
+}
+
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abhigargrepo wrote:

Added a test function to check for llvm.set.fpenv intrinsics
 

https://github.com/llvm/llvm-project/pull/88858