summaryrefslogtreecommitdiffstats
path: root/llvm/lib/Target/AMDGPU/SIInstrFormats.td
diff options
context:
space:
mode:
Diffstat (limited to 'llvm/lib/Target/AMDGPU/SIInstrFormats.td')
-rw-r--r--llvm/lib/Target/AMDGPU/SIInstrFormats.td14
1 files changed, 13 insertions, 1 deletions
diff --git a/llvm/lib/Target/AMDGPU/SIInstrFormats.td b/llvm/lib/Target/AMDGPU/SIInstrFormats.td
index 5f260ba0c85..16021fff531 100644
--- a/llvm/lib/Target/AMDGPU/SIInstrFormats.td
+++ b/llvm/lib/Target/AMDGPU/SIInstrFormats.td
@@ -229,7 +229,19 @@ let Uses = [EXEC] in {
class VINTRPCommon <dag outs, dag ins, string asm, list<dag> pattern> :
InstSI <outs, ins, asm, pattern> {
- let mayLoad = 1;
+
+ // VINTRP instructions read parameter values from LDS, but these parameter
+ // values are stored outside of the LDS memory that is allocated to the
+ // shader for general purpose use.
+ //
+ // While it may be possible for ds_read/ds_write instructions to access
+ // the parameter values in LDS, this would essentially be an out-of-bounds
+ // memory access which we consider to be undefined behavior.
+ //
+ // So even though these instructions read memory, this memory is outside the
+ // addressable memory space for the shader, and we consider these instructions
+ // to be readnone.
+ let mayLoad = 0;
let mayStore = 0;
let hasSideEffects = 0;
}
OpenPOWER on IntegriCloud